Description

Audio Note, WE-91A, Rega, Ayon
1/20/12 -I built a 300b single ended triode amplifier based on Joe Robert's Western Electric 91A. Used all vintage caps and vintage resistors-Alen Bradley and Ohmite. These vintage parts came from Leeds Radio just a few subway stops from my apartment in Brooklyn. The coupling caps are .1uf V-Cap TFTF. Large motor run oils in the power supply. Sophia Electric 91-05 Opt transformers and Sophia Princess Mesh Tubes. Stancor PT's came from ebay.

3/2012: Replaced the Alps Potentiometer with a Goldpoint 50K stepped attenuator. More clarity and transparency through the entire frequency range.

Still not using a pre amp.

5/12- Replaced the oil capacitor C-3 biasing the 6C6 with a Black Gate.

6/6/12- Finished new chassis

7/12 - Added Rega P3-24 with Power Supply and Exact Cart. Will look at different cart options later

7/12 - Pulled the 24 gauge silver hookup wire used throughout the amp and installed 16 gauge pure copper wire. The 24 gauge wire gave the sound a weightless quality that I did not like.
The 16 gauge has been in for three weeks and I can report that the weight and depth has very pleasingly improved. Vocals have an added pleasing quality. Instruments throughout the entire frequency range have more depth and richness. The low end is more powerful. I can more easily perceive the stage that the players are performing on.

10/12 Pulled C-5 and didn't replace it. Pulling this capacitor has changed the sound of this amp. Clarity and detail throughout but especially in the lows thru the mid range. Much easier to detect decay and the accompanying reverb. Dynamics seem more unconstrained as well. It has decreased gain by around 20% but in my room with the AN-e's it does not matter.

1/2013- Replaced the 1k Allen Bradley 6C6 Cathode resistor with a Vishay TX2575. This resistor is very neutral...almost as though it has no sonic character of its own. Each instrument has its own accurate color and detail but not at the expense of the overall musical message. Took about 100 hours of break in time.

2/16/13--After a month with the TX2757 in the 6C6 cathode position, including bypassing them with Black Gate Caps I decided to pull these resistors. They did not provide the richness and room filling sound that the A-B's and the older AN Tantalum did. A few weeks ago I got two of the most recent production 1k An Tants from the Hi Fi Collective.

These new Tants are more closely akin to the A-B's than to the TX2575's. They are not as sonically accurate or pure as the TX's. But they do fill the room with rich satisfying music like the A-Bs but with more detail and without the extra noise or warmth or whatever it is with the A-B carbon comps. Still running the amp without the 6C6 bypass cap.

2/2013--Built a home brew phono pre amp using the Audio Note M3 schematic.

4/2013-Upgraded to the Rega White belt and Groovetracer Reference subplatter. Excellent sonic improvement.

5/2013- WE91a amp---Replaced the the screen cap (6C6) which was an oil with a 12uf Solen cap. Have about 50 hours on the Solen. Not sure I like it. Makes the amp sound a little cold and forward. Will live with it for a while.

Late 5/2013. The 12uf Solen has broken in and I like it better than the oil that it replaced. Warmth but with plenty of detail.

Mid 7/2013 (Audio Note DIY Phono pre) ---- Added Audio Note Tantalum resistors into the signal path. 7/27/13-took out the .047 and .33uf Solen caps in the signal path of the phono pre and added .047 Vcap TFTF and .33 Audio note copper caps.

8/11/13 (Audio Note DIY Phono pre) After two weeks with the Vcaps and AN copper caps in the phono circuit my vinyl rig is a lot fun to listen to. A more beautiful and open sound than with the Solen caps.

10/12/13 WE91a---
replaced the 15uf oil cap that was biasing the 300b tube with a polarized 22uf Black Gate. Will listen for a while and see if I like it.

11/1/13 WE91a
The Black Gate by itself is still fine.

I cleaned the resistor and Cap leads, tube sockets and tube pins with 99% alcohol. They have been in the cicuit for 2 years and were tarnished and very dirty. Once cleaned much more mid range clarity and cleaner bass.

11/20/13 Added Gold Lion GZ34 Rectifiers. Sound is open and airy. Very nice

12/28/13 Added Emission Labs 300bXLS.

2/17/14- Audio Note Home Brew Phono Pre-Finished new chassis for the Power supply.
Added 8 more Tantalum Resistors (4 per channel) to the Phono circuit. Now the circuit has a few A-B's and 6 Tantalums per channel. Phono pre sounds a lot better than it did with the PRP red resistors.

3/16/14 WE91A. Because the EML300bXLS tubes are so well internally balanced, I was able to remove the Hum pots and still use AC heat. Now the 300b bias is going thru the center tap of the 5volt filament transformer. Without the hum pots, the sound is much freer and alive. I am liking this!

3/31/14-AN Phono Pre. Replaced several more PRP resistors that were on the plate of both the PS and circuit with Mills. Hopefully they will sound better than the PRP's

5/1/14 WE91a. Took out the Allen Bradley grid leak resistors and replaced with Shinkoh Tantalun resistors. took about two weeks to break in.
5/25/14 WE91a. Put the Allen Bradley grid leak resistors back in. The Shinkoh Tants made the amp have a glare that didn't go away even after the resistors were broken in.

Running the Amp at 425V B+ is sounding good with EML 300bXLS and GZ34's.

6/7/14 AN Home Brew Phono Pre-
Took out the last PRP resistors in the circuit and replaced with Allen Bradleys. Very nice change. Now the circuit has a good mix and Tants and Allen Bradleys. There are a few more PRP's in the power supply that I will replace very soon.

6/22/14 AN Home Brew Phono Pre- Took out the last of the PRP resistors in the power supply and replaced with Mills resistors

9/23/14 AN Home Brew Phono Pre - Installed Audio Note Copper Capacitors in the RIAA network. .0028uf and .0082uf in each channel

11/21/14 AN Home Brew Phono Pre - Replaced the six more Allen Bradley resistors (3 per channel) with Takman one watt resistors.

11/28/14 AN Home Brew Phono Pre - Tweeked the voltage in my phono pre. Very good results. Much more open and transparent sound. Orchestral strings sound really nice.

12/6/14 Rega P3-24. I added a Audio Note iQ3 cartridge. Needs about 100 hours of break in.
Rega Exact is a great cartridge but opportunity came up. We'll see which I prefer once the iQ3 is broken in.

12/13/14 WE91a. installed Duelund Copper Cast coupling caps. After two weeks more natural sounding than the V-cap Teflon

1/12/15-Duelund Copper CAST 630v coupler caps have a very natural, emotionally engaging musicality with a very rich and colorful tonal pallet. Keepers for sure!

3/1/15-WE91a - Experimenting with WIMA power supply caps. These are Metallized Polypropylene. C2 in my power supply is a 100uf oil. I have replaced it with a 50uf Wima. I think the 50uf is a better choice as it controls the woofer a bit better.

3/7/15- WE91a - Added new custom built power transformers by Heybour. 250mA. Also added another WIMA cap at C1- its a 15uf.
B+ went from 424 to 450. 375v across the 300b plate. 76mA. With all these changes the amp has better control over the woofer. Punchy bass.

3/25/15 WE91a. Took out the Wima at C1. Made the amp sound harsh. Put it a GE F97 oil.
3/30/15 WE91a. Took out the Solen 12uf Cap on the screen of the 6C6 driver tube and replaced it with a 22uf Black Gate VK cap. The Solen is muddy compared to the Black Gate. I didnt realize how important the cap on the 6C6 screen is to the sound of the amplifier.

4/15/15 WE91a - A friend has lent me four low DCR 2H chokes (two per channel) to try in place of the single 10H Hammond in each channel. PS is now 15uf/1.8H/15uf/2h/50uf. Amp sounds faster and more nimble. Nice.

5/14/15 WE91a. I have bypassed the Wima Cap at C2 in the power supply with four very low value film caps. Too soon to draw any conclusions about sound.
5/31/15 WE91a. New production Audio Note 50uf Kaisei Power supply capacitors have arrived and after a week of burning them in, I have installed them in place of the Wima 50uf and all of those bypass film caps. will see which I like better in a couple of weeks.

6/13/15 WE91a. The New production Audio Note 50uf Kaisei Power supply capacitors have been in my power supply for two weeks - about 100 hours or so of playing time. They have a purity, and a crystal clear clarity that no other cap in the power supply has had. I am going to replace the rest of the PS oils with these to see what happens. Maybe it will be too much- who knows. They dont have too much of a sonic signature. They just sound very free and open so adding a few more may be ok. If not I can put an oil back in.

7/10/15-WE91a. Installed Audio Note Ultra Hi B output transformers today. Will need a few weeks to come around.
9/1/15 - WE91a. The Audio Note Transformers and great with excellent depth and coherence. Added copper shrouds. 
9/25/15 -Western Electric Speaker wire and interconnects. I like the speaker wire better than my Audio Note Lexus copper. More direct. They make the Lexus cable sound soft around the edges and diffuse. The WE Interconnects are very good too. But still learning about there sound.
10/11/15 - WE91a. Took out the 6C6 driver tubes and installed C3m drivers. 

11/28/15 - WE91a. Added Regulation to the Screen of the C3m driver tubes. K&K CCS board and an OD3 glow tube that is puts out 150volts. The C3m driver tube and regulation is an excellent driver of a 300b output tube. Very fast  and dynamic with lots of detail and musicality. I am very happy with the sound of this amp.  Probably not making any more changes for quite a while.

1/1/16 - WE91a I still notice a bit of extra weight in the lower mids so I replaced the last oil cap in the power supply (c-1) with an Audio Note Kaisei 50uf cap.

2/1/16 -WE91a. After adding additional Audio Note Kaisei capacitor to the power supply, the voicing of this amplifier is complete. The power supply is 50uf/5h 30ohm choke/ 50uf and it sounds dynamic fast and clean. With all Kaisei caps in the power supply the lower mids are now more open and that weight I mentioned above is gone. Will rebuild the amp onto a new piece of wood and hide all of the hi voltage parts underneath. Will post pics of the new build as it progresses.

3/10/2016 - WE91a.  New Chassis is finished. The new build features and extremely short signal path and a copper box known as a "faraday cage" which isolates the audio circuit from RF/AC, Cell phones, and other nasty's. The goal here is to eliminate the grid stopping resistors that are usually necessary on many tube grids. In a SET amplifier any extra part effects the sound especially a resistor in series with the grid. They are usually necessary on the C3m grid as well. Without a grid stopper the C3m tube can squeal and make all sorts of other very harmful noises but with my new chassis implementation I have not needed a grid stopper.  If the C3m tubes continue to behave it would be a major step forward. The sound of the amp without a grid stopper is more open free and natural.

4/2/16 - Audio M3 Phono Pre- I had some copper left over from my amp build so I made a 8x6x2 copper box and put the phono circuit inside. Pics added.

5/16- Bought Kondo KSL-LP silver interconnects and am using them with Audio Note Lexus Bi Wire copper speaker cables. After trying various IC's like homebrew WE-16g and Ocellia silver reference and various Speaker cables like WE-16g and 10g and Kondo KSL-SPz, the Kondo KSL-LP silver interconnects with Audio Note Lexus Bi Wire copper speaker cables really bring something special to the table at least to my ears system and room.

9/20/16 Ayon CD07 - put in NOS Raytheon 5687 tubes and after a week of break in they sound tremendous. Transparent mids fast and clean lows and clean extended highs. Better than any tube thus far.

10/2016  WE91a - I removed the 91k bleeder resistor from the last cap in the power supply. I can't believe how much more open, free and transparent the sound is. It's like that bleeder had clamped down on PS and now without it there is more energy coming into the room. Any tonal warmth that had been left in this amp is now gone.

11/2016 WE91a - with the bleeder resistor removed I noticed a tinniness in they high frequencies so I removed the GE 12gauge wire from both the power supply b+ and ground and replaced it with vintage WE 16gauge wire and that tinniness is now completely gone. The WE vintage wire sounds very good just as others have reported.

1/2018 -WE91a. Replaced the Goldpoint 50k stepped attenuator with a Seiden Shunt stepped attenuator loaded with Audio Note tantalum resistors. Its been in for about a month and I am shocked at the change in sound. Extended highs and lows and more lively mids. Huge step up. The highs and mids are so open and beautiful. Powerful bass. A very worthwhile change.

3/2020- WE91a.  Over the past year and one half, experimented with a .22UF Russian vintage cap in the coupling position in place of a duelund .1uf copper cap after growing tired of the  accurate and analytical presentation of the Duelund. The Russian cap did not do anything that I liked even after a year of listening. It was kinda like all the instruments turned the color of grey. I’ve had some Audio Note copper .47uf caps sitting around for a few years so put them in around the first of 2020 so they now have three months on them. 

The AN copper .47uf coupling caps after a two month an up and down ride stopped changing about a month ago. So I’ve been listening for a solid month after they finally settled in.  

I perceive no less detail with them compared to the duelunds but the detail is integrated into a more musical and three dimensional presentation. There are real instruments playing in front of me. Much more texture and dimension. There may be just a bit of glue tying everything together but even with the glue, there is individual instrumental color and tone in spades. A bit more overall warmth and richness.  Keeping in mind that my system has AUDIO NOTE output transformers, speakers, speaker cables, resistors and capacitors, kondo interconnects and an AN IQ lll Cartridge. So I would have thought adding an Audio Note coupling cap would have been to much, but it actually brought everything together in a very nice way.

 I think they might be too much of a good thing in a system that already fills out a three dimensional space but for me they add something lovely and musical that was missing. This reminds me that there is no such thing as the best capacitor or best anything else....

Read more...

Room Details

Dimensions: 25’ × 12’  Medium
Ceiling: 9’


Components Toggle details

    • Audio Note UK Audio Note UK AN-e LX HE
    Fun to listen to speakers that do a nice job with most types of music
    • DIY WE91a
    Very natural sound amp with good pacing. Duelund Copper cast caps. Audio Note Ultra hiB Output Transformers. Very short signal path and power supply wiring.
    • DIY Western Electric WE-91A
    Old breadboard

Comments 326

Showing all comments by jetrexpro.

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Owner
Hi Jond. Those are Super or Ultra hi B AN transformers. I don’t remember which. I got them from an Audio Note dealer about 6 years ago. They say Mishue silver on them so they would probably go into that type amp, but they have copper primaries and copper secondaries.

jetrexpro

Owner
Hi Jo, I have always wanted to hear Kondo copper IC’s. I’ve heard they sound amazing. Your Auditorium 23 coppers would be a great listen I’m sure. I love my Silver ICs but would love to hear what a great pair of copper ICs sound like. If you ever in Brooklyn NY pls let me know.

Hi Dan, great to hear from you. I’ve been enjoying my system for years now. Once I changed my amps Power Supply to 5r4wgb potato mashers and put in a Seiden shunt stepped attenuator that was the end for changes. Hope you are well and doing great. Best to,you! Jet.

jetrexpro

Owner
Hi JO, Wow, We do seem to be on the same road to good sound! Have always been curious about Kondo copper IC's. I bet they sound fantastic. Such a nice surprise that AN copper caps would sound so good and better in my system than any other cap i've tried.
The dimensions of my amp is 18 inches wide and 19 inches deep. Way too heavy. Wish I had built mono blocks. Yes the faraday cage was a very nice surprise to find our how quiet the amp sounded with this in place. Take care JO!

jetrexpro

Owner
Hi Tjkurita, so nice to hear from you! 
the audio note cap I used in place of the duelunds was .47uf copper. I see in your system page that you are using audio note .22uf silver. Depending on how the rest of your system is wired and sounds, you could try audio note copper .22uf and it will be a different sound than the AN silver cap but it will still share that audio note musicality and house sound. Ive never heard an AN silver cap in my system so I have no idea the real difference. But if your system is a bit lean, a copper cap might be the ticket.
Parts Connexion has the copper caps for $55 each so trying them would not break the bank. Although the break in is a pain....about 200 hrs.  This has taught me it’s about finding the right part, not the most expensive. I’ve been reading the Steve Hoffman post “strictly for fans of audio note” and have learned that audio note does not install silver parts or recommend silver cables unless the rest of the system will benefit from it. Anyway, just a thought. If you are looking for a different sound you could try a cap that is a lot less expensive than the AN Silvers and the Duelunds. Take care, jet

jetrexpro

Owner
Hi Dan, nice to hear from you too. I wanted to put the duelunds back in before posting this update, but there really was no looking back. The duelunds simply did not sound anything like these audio note copper coupling caps. 
One more thing. I wish I had put in a Seiden shunt stepped attenuator loaded with AN Tant resistors from the very beginning instead of the Goldpoint stepped attenuator. I really don’t understand how this is possible since the Goldpoint is so well thought of, but the highs were so restricted with the Goldpoint that I made many changes that were probably not necessary if I had known and simply bit the bullet and spent the extra money on the Seiden shunt stepped attenuator from the very beginning. Take care Dan!

jetrexpro

Owner

Thanks Cymbop. Much appreciated. 

A report an my WE91a amp after a long journey of coupling caps.

Over the past year and one half, ive experimented with a .22UF Russian vintage cap in the coupling position in place of a duelund .1uf copper cap after growing tired of the  accurate and analytical presentation of the Duelund. The Russian cap did not do anything that I liked even after a year of listening. It was kinda like all the instruments turned the color of grey. I’ve had some Audio Note copper .47uf caps sitting around for a few years so I put them in around the first of 2020 so they now have three months on them. 

The AN copper .47uf coupling caps after a two month up and down ride stopped changing about a month ago. So I’ve been listening for a solid month after they finally settled in.  

I perceive no less detail with them compared to the duelunds but the detail is integrated into a more musical and three dimensional presentation. There are real instruments playing in front of me. Much more texture and dimension. There may be just a bit of glue tying everything together but even with the glue, there is individual instrumental color and tone in spades. A bit more overall warmth and richness.  The bass is huge compared to the duelunds. Keeping in mind that my system has AUDIO NOTE output transformers, speakers, speaker cables, resistors and capacitors, kondo interconnects and an AN IQ lll Cartridge. So I would have thought adding an Audio Note coupling cap would have been too much, but it actually brought everything together in a very nice way.

 I think they might be too much of a good thing in a system that already fills out a three dimensional space but for me they add something lovely and musical that was missing. This reminds me that there is no such thing as the best capacitor or best anything else....take care, Jet

jetrexpro

Owner
Hi Gunther, if at all possible use copper for the top plate. Will very likely sound better than wood. Wood has a sound. When I changed from wood to copper in my phono circuit, the change was very positive. Have a machine shop drill the holes for the tubes, etc. please read about faraday cage and try to use that in your design too. Make sure you have plenty of ventilation. Regards Jet

jetrexpro

Owner
Hi TJ. Thank you and nice to hear from you. If you are in the neighborhood give me a shout. Take care Jet

jetrexpro

Owner
Thank you Dan. Nice to hear from you. Hope all is well with you are your system. I’ve been working on the amp throughout 2017 making small changes. After a month with a shunt attenuator I felt compelled to post my findings. The shunt attenuator has only two resistors in the signal path and really only one that is directly in the signal path. I was not aware how much the goldpoint was holding back the potential of my amp and system. Ouch.

jetrexpro

Owner
 Replaced the Goldpoint 50k stepped attenuator with a Seiden Shunt stepped attenuator loaded with Audio Note non magnetic tantalum resistors in my WE91a amp. 
Its been in for about a month and I am shocked at the change in sound. Extended highs and lows and more lively mids. Huge step up. The highs and mids are so open and beautiful. Powerful bass. A very worthwhile change.
I was told replacing the Goldpoint with a shunt attenuator would be a pretty big step up but a was not prepared for this. 

jetrexpro

Owner
Since the beginning of 2017 I've been changing the power supply of my amp from the 5AR4 indirectly heated rectifier to the 5R4WGB potato masher directly heated rectifier.  The change has been well worth it and the result is a much bigger soundstage and instruments that are more palpable and fleshed out.
One of my friends who is very familiar with Audio Note design was responsible for suggesting this change. 
Since the 5r4wgb drops a lot more voltage that the 5r4 a complete reworking of the power supply was necessary to keep the voltages on the C3m and the  EML300bXLS tubes in their sweet spots. Regards Jet.

jetrexpro

Owner
Thank you Devilboy and Islandman. Building and voicing this amp over the past four years has been an education. especially the voicing part of the journey.  Especially the power supply. Which brings me to another change I made in the power supply a few weeks ago.


I removed the 91k bleeder resistor from the last cap in the power supply from my WE91a amp and I can't believe how much more open, free and transparent the sound is. It's like that bleeder had clamped down on PS and now without it there is more pure open musical energy coming into the room. And not by a small margin.

I had been concerned with extra warmth that had been left in this amp and now that warmth is gone. What's left is fast, transparent and full of energy and dynamics but still with that 300b texture. With Audio Note speakers which are warm sounding, still a warm and engaging presentation.

with the bleeder resistor removed I noticed a tinniness in the high frequencies so five days ago I removed the GE 12gauge wire from both the power supply b+ and ground (which I noticed sounded tinny when I tried it as speaker wire) and replaced it with vintage WE 16gauge wire and that tinniness is now completely gone. The WE vintage wire sounds great just as others have reported. The WE16g is also adding to the transparency. Very nice sounding so far. The wire was broken in since I have been using it as interconnects but the sound is still changing a bit using it as hook up wire since there is a lot more voltage and current flowing through it. But so far l really love the sound. It's clean and clear but with beautiful 300b tonality.

The bleeder resistor in the power supply is there in bleed off voltage from the power supply caps when you turn off the amp so it's ok in my amp to remove it. It's only a problem if you plan to work on your amp. Before you do you should bleed off the residual voltage before starting work.

jetrexpro

Owner
had some copper sheet left over from my amp build so I shaped it into a box and put the very sensitive phono circuit inside. Lots of pictures.

jetrexpro

Owner
Thank you Dan!
The sound is a bit different now. The old chassis was made mostly of tiger maple and it added some warmth and colorations. The new chassis has a lot more metal and the wood is a harder wood from Africa. The sound is now a bit clearer and cleaner. Detail seems more exposed. The noise floor has probably dropped but that is harder to pin point since all these changes took place at the same time. I like the sound so far but it's also a matter of taste how much warmth vs detail one wants in their system. There is still plenty of that 300b texture so I am happy :) it's also nice to hear the Audio Note AN-e's respond to these subtle changes. After four years with these speakers I love them even more. 

jetrexpro

Owner

Amp is finished, and passes audio! whew! what a relief. Always scary when firing up the B+ for the first time. Also so far with the close signal path and copper cage around the circuit there turns out to be no need for a grid stopper in the C3m input/driver tubes. The amp sounds much better without grid stopping resistors.

I posted pictures that show from start to finish building the amp -Regards Jet

jetrexpro

Owner
added some pictures of building a new chassis for my 300b amp. This new version will have all the hi voltage parts hidden underneath.

jetrexpro

Owner
I also wanted to relate my ongoing thoughts about the homemade Western Electric 16ga shielded interconnects which are terminated with Canare F10 RCA plugs. Now that my amp has so much more inner clarity and detail I am finding more synergy with the Kondo KSL-LP interconnects that with the WE interconnects. After changing the driver tubes on my amp from 6C6 to C3m and regulating the screen on the C3m and then adding more Audio Note Kaisei capacitors into the power supply the Kondo ICs seem to compliment this added clarity with their own natural and delicate musicality. Before making these changes to my amp, the Kondo ICs seemed too polite and not as musical as the WE ICs. Now the Kondo ICs don't sound polite at all. They sound in perfect harmony with my amp and speakers. Music sounds natural and beautiful but also when called upon they can sound loud and crazy. When the music dictates this kind of loud presentation I am hearing the sound leaping into the room. Before the Kondo IC didn't respond as well as the WE ICs did to the many types of music I listen to. So now I am hearing from the Kondo all and even more of the musicality I do from the WE ICs but with the Kondo's inner clarity and extended frequency response. Very interesting developments indeed. Jet

jetrexpro

Owner
Posted a picture of the beginning work on rebuilding my amp on a new piece of wood with all of the electrical components underneath. After installing Audio Note Kaisei capacitors throughout the power supply, I can report they are very open sounding and have done nothing but improve the sound of this amp. Excellent clarity throughout the frequency range. 

At this point I am still deciding the position of the tube sockets, the capacitors and the filament transformers. As progress continues I'll post more pictures of the rebuild.

I have been voicing my amp over the past four years by ear and changing only one part at a time to arrive at this final version. I am done so its time to rebuild the amp so my wife is not afraid of it :) Regards Jet

jetrexpro

Owner

Manga, Correct, the original Thorsten Loesch "Legacy" used the SV83 tube as the driver but he changed it to the C3m. If you google Thorsten Loesch Legacy, you'll find the article that talks about the changes.

Pentodes driving DHT (WE91a) lend a very natural tone and pacing to recorded music. I don't know why, maybe its the simplicity of the circuit but when listening to especially Jazz, the music just breathes. One of my musician friends actually used those words after an afternoon of listening.

And if I know I am going to listen to Jazz on vinyl, I'll take out the 5ar4 rectifiers and put in Mullard GZ37's (CV378) which lowers the b+ and lets the amp truly relax. With vinyl and these rectifiers I hear the give and take, push pull of the groove that the musicians are laying down. When listening to Pop, Rock and classical, I prefer 5AR4's. With these Rectifiers the amp has more jump and dynamics. 


jetrexpro

Owner
Grannyring, I posted some pictures of the CCS and OD3.

jetrexpro

Owner
Hi Manga,  I am running the C3m tube at the operating points suggested in the Tube data. 225v on the plate, 150v on the screen and a 270 ohm resistor from cathode to ground. This gives me a 75v swing. At these operating points the 16mA operating current should drive the 300b very nicely. These are Thorsten Loesch's "Legacy" amplifier operating points as well. Your example OP's look a little bit like Yamamoto's C3m/300b amps OP's. I found their schematic on line. We'll see how the sound fleshes out over the coming weeks. I was pleased before I installed the CCS and even more so now. I sincerely hope to hang up my soldering gun for a while :)  Thank you for thoughtful post. Its great to have a community of folks so willing to share their thoughts and ideas. Regards Jet

jetrexpro

Owner

Salectric, I'll try the grid Riken grid stoppers once I am sure the CCS has settled in. Should be able to try them by this coming weekend.

Grannyring, The K&K CCS board does not have an octal socket for the OD3 tube. You'll need to buy that separately. In my case I needed 150 volts on the C3m screen and the OD3 puts out 150v. The way I set the CCS voltage was to use a 9v battery and a 10 ohm resistor hooked in series with the positive side of the CCS board and measure the voltage drop across the resistor. The instructions in the K&K manual on how to set the voltage were not very helpful and Salectric came to the rescue on this and several other parts of this CCS project. If you want to see the schematic that I drew message me and I'll send it to you.

The cool thing about this regulation was I was able to remove two resistors and a capacitor from the C3m screen. That may have as much to do with the increased detail and musicality of the amp as the regulation itself.

jetrexpro

Owner
On Saturday I installed voltage regulation on the screen of the c3m driver tube of my WE91a amp. The regulation consists of a K & K constant current source board and an OD3 RCA glow tube. This circuit holds the screen at a constant voltage. Thank you very much to Salectric for all of his help and advice during this process.

With Regulation on the screen the sound of the amp is very very clean and very present. I think the circuit is still breaking in so there may be more improvement ahead. After I installed it my wife and I were listening and she said "don't do anything else to this amp. Anything else you might do could only harm how the amp sounds now." Anyway she is right and I am done. Pretty much no more tweeking. After an eight month process the amp sounds really nice and I am happy to hang up my soldering gun for a while. The only thing I could possibly consider doing would be build a choke loaded power supply much later on. Regards Jet

jetrexpro

Owner
Bill I heard from another DIYer that has some experience with Audio Note Kaisei caps and he has not heard any glare. To be fair I am using them in several positions in my amp and am not hearing glare other than what I reported above. I am using a 22 uf on the plate and a 100uf on the cathode of the C3m driver tube and a 55uf in the last cap of my amplifier's power supply. I don't think the Audio Note guys would build caps that have glare. But I still don't know why I did have the glare I reported above.

I'll be installing voltage regulation this weekend. Jet

jetrexpro

Owner
The bleeder resistor across the last cap in my power supply has a pretty big influence on the sound of my amp. If you could get away without using it, it might be a nice improvement in sound. Or if you need to keep it in you can try different brands of resistors to find out which brand sounds best.

jetrexpro

Owner
Bill, In my power supply the bleeder serves only to bleed voltage out of the caps when the amp is turned off. In some power supplies bleeders serve other protective functions. Please make sure you can safely remove them.

Once I try regulation on the C3m screen I'll report back. Regards -Jet

jetrexpro

Owner
Hi Bill, your pre amp is very ambitious. Like Charles I am very interested to know how it sounds once finished. If you are like me once it’s done you'll end up doing some tweeking to get the sound just right to suit your tastes. I am still amazed at how very small changes greatly affect the sound of my WE91a 300b amp. It’s actually a bit intimidating. The more I mess with this amp the more I realize I don’t know….a real journey.

As for the Audio Note Kaisei Electrolytic capacitors I do like what it does in the last cap of the power supply in my WE91a amp with this warning. When I removed the “bleeder” resistor across the 50uf AN Kaisei the sound changed and there was an ugly glare. I don’t know why removing the resistor caused this. Once I put the bleeder resistor back in the sound returned to normal. I do remember how much I liked this capacitor for its open spacious sound and still do with the Bleeder resistor in place.

I did have an 5uf Audio Note Kaisei Electrolytic capacitor filtering the screen of my newly installed C3m driver tube but during the first few weeks that this 5uf cap was installed the amp was not making music and there was a bit of glare in the upper mids. When I removed the AN 5uf Kasiei cap the glare went away and the amp opened up and made music. I don’t know if it’s the AN cap’s fault or if it was the fault of my circuit design. Yes it’s my design so I am treading in deep water here. I am using a 22uf Kaisei capacitor to filter the C3m plate and so far this Cap sounds very good. There is more tweeking to be done including regulating the C3m screen voltage but I’ve been very happy with the amp as is I have delayed installing the CCS/OD3 regulation. I may try this over the long Thanksgiving break.

So at this point Bill, the Audio Note Kaisei Electrolytic capacitors are probably worth a try but I would not go crazy buying a bunch of them just in case they don’t work for your Hydrid Lector amp.

jetrexpro

Owner
Thanks Guys.
It was interesting over the past several weeks to hear the amp NOT making music:)

I'll add voltage regulation in a week or two depending on when I have time.

jetrexpro

Owner
It's been three weeks since I replaced the 6C6 driver tubes in my WE91a 300b amp with C3m driver tubes so it's time for an update since all the parts should be broken in. For the first two weeks I suffered while all the capacitors and resistors and the tubes took their sweet time breaking in. One thing that was clear from the beginning was how much more extended the high frequencies were compared to the 6c6 tubes. Also once the sound gained some weight and gravitas that cheetah speed slowed a bit. So the amp's pacing is a bit more natural.

After about two weeks I was pretty sure the parts and tubes were broken in but the amp was not making music and sounded pinched and tentative so I pulled the grid stopper resistors and wow that stressed pinched sound went away and the sound started to come alive. Grid stopper resistors are included in many amp designs but I can say from this experience they killed the musicality of my amp.

But after a few days the amp was still not making emotionally connecting heart warming music like it did with the 6c6 drivers and I was hearing some
upper midrange glare, so after some email conversations with Salectric (thank you Salectric!!), I pulled the 5uf capacitor that was filtering the screen voltage.
Salectric thought I had enough filtering already and advised me to try pulling
it. Now this is when the amp started to cook! The highs and upper mids became extended, gorgeous and filled the room with an air and space that I had not heard before from this amp. The mids are very clean and clear but also rich musical and emotionally engaging. These C3m tubes possess a lit from within sense of refined touch and a clean texture. This is where the magic is happening and makes the 6c6 tube sound a a bit muddy and wooly by comparison. This lit from within expression extends through the entire frequency range. As I mentioned above the highs and upper mids are pretty special.

Another highlight is how clean the lower mids are. Clean but still fully expressed with weight and depth. They add to what was already happening when I added the Audio Note output transformers. Of course electrically the C3m tube is much better equipped than the 6c6 tube to drive the 300b tube.

So yes the amp is finally making expressive emotionally engaging music. There is more that I can do to the circuit that may yield even further improvement. Salectric and I have been discussing regulating the screen voltage. I've got the parts to do it. It would eliminate three more resistors and one more capacitor. Most folks who use the C3m tube employ some kind of regulation and the screen of this pentode is very sensitive and should respond quite favorably to a regulated voltage.

It took a few weeks of suffering but I am finally very excited by the level of
music making this amp is producing. The 6c6 driver tube is justly famous for its beautiful musicality that is emotionally connecting, but after some work the C3m driver can be even more beautiful sounding with even more potential for musicality and excellent coherent fidelity. Jet

jetrexpro

Owner
The C3m driver tubes have been installed for about 24 hours so I would not say anything specific about their tonal characteristics since they and some of the bypass caps are new but it is interesting to hear how different they handle dynamics when compared to the 6C6 tubes they replaced. The C3m drivers are VERY fast and very dynamic when compared to the 6C6 drivers. The C3m's sound modern and the 6C6 have a more relaxed older sound. I don't know if that is the right way to put it but at this point the amp sounds like a cheeta. This may change as the tubes and caps break in. The 6C6 drivers have a very natural slightly layed back pacing which I love. These C3m's are super speedy at this point.

Many technical guys say the 6C6 is not up to the task of fully driving the 300b and are slightly rolled of at the frequency extremes and the C3m suffers none of these technical draw backs. But the proof is in how the amp sounds and not about technical specs. More about these this coming weekend -Jet

jetrexpro

Owner
Grannyring, Looking forward to hearing more about your Electra Fidelity amp.

I added copper shrouds to my AN Ultra Hi-B output trannies about a week ago and the amp's performance has taken another step up. The extra detail on top of the other superior attributes of these trannies leaves me shaking my head at the musicality of my amp. This makes me very cautious about changing driver tubes at this time as I am loving the 6C6 driver tube.

This is what Audio Note writes about the copper shrouds:

"the copper shroud being non-magnetic improves not only RF influx, but also low level behaviour as it does not short out the airgap on the higher permeable cores like the AN Ultra HiB and the nickel cores this is essential for optimal performance."

jetrexpro

Owner
Charles, The C3m tube is also used in the Shindo Vosne Romanee. The DIY community is enthusiastic about the C3m saying it drives a 300b much better than the 6C6. Some like its sound better than the 6sn7 which you reference above. I love the sound of the 6C6 tube - so natural with great pacing so yes this will be very interesting. When I remove the 6C6 tube I will leave all the resistors and capacitors attached to it so if I end up not liking the C3m, I can reinstall the 6C6 without much trouble. Your Franks which use the 6em7 triode as a driver is one of the top 300b amps. I heard Snopro's Franks and felt like I could come home to that sound anytime!

Grannyring, I have en extra set of Switchcraft RCA plugs and some more WE16ga and will build a third set of IC's with the Switchcrafts. Eventually I'll have several IC's to compare. The shielding finally arrived so at some point I'll throw that into the mix as well. In my system the Canare F10 sound smooth from top to bottom with lots of midrange texture.

I briefly listened to the WE 22ga solid core ICs last night and they sounded closed in lacking any texture and color so they will need lots of burnin time.

jetrexpro

Owner
1markr. I don't know. Hope you got your answer.

Update WE16ga Interconnects- I have been listening to my WE16ga interconnects with Canare F-10 RCA plugs for several weeks and I like them very much. Better than the WE16ga IC's terminated with no name RCA plugs. The Canare plugs have a richer and smoother and more room filling mid range. My wife and I both heard the difference which is pretty significant. I still have not tried shielding yet.

Last night I built another pair of WE IC's using 22ga solid wire and SwitchCraft RCA plugs. Two runs of wire per positive and negative with a pretty tight twist. More on the sound of these later.

In my Western Electic 91a amp, I am a few days away from pulling the 6C6 Pentode driver tubes and replacing them with C3m Pentodes. Lots of differences. C3m tubes draw more current and have 20 volts on the filaments. Many feel the C3m pentode is one of the best sounding driver tubes for a 300b amp. I'll find out! - Jet

jetrexpro

Owner
Hi Brett I tried calling you this evening could not leave a message. I messaged you through the agon system

jetrexpro

Owner
Brett I call you. With no wife to tell me what to do, the living (listening) room has vinyl and WE wire strewn all over the floor. If I know what is good for me I'll have it cleaned up before she gets back in town early next week :>)Jet

jetrexpro

Owner
Grannyring I've heard the Abby's with a 45 amp. I bet they are being driven very nicely with those firm 11watts. Near field must be intoxicating. Charles and I were living vicariously through your 845s and are now having withdraw symptoms :)

jetrexpro

Owner
Grannyring is the el34 amp broken in? Great that you have both nude and shielded WE ICs. Sounds like they will both come in handy. I plan on doing the same. Haven't got around to building the shielded pair yet but will do soon. Will be looking forward to your updates. Jet

jetrexpro

Owner
Grannyring, I'm kinda bummed that you got rid of your 845 amp since it was so good. You'll have fun and the EL34 amps should sound really great since he makes them from the ground up with his own OPT trannies. Wonder if he makes his own PT's.
Looking at the schematics on Jack's website he uses solid state rectification for all his amps and preamps.

jetrexpro

Owner
Grannyring, Sounds like you have ordered an Electra Fidelity EL34 amp. You mentioned SS regulation. Does it also employ solid state rectification? You'll have these EL34 amps, your 845's and 300b's all to compare driving your Lahave's. 3 very different tubes types.

jetrexpro

Owner
:) I just priced Audio Note Silver secondary Ultra Hi B double Core at HIFI collective and they are $4,047.29 for only one transformer. LOL!

jetrexpro

Owner
I just went to the Electra-Print website and it looks like you can get partial silver secondaries rated at 100mA for well under $1000. Good info from Salectric about the possible advantage of ordering only one secondary tap and how good the PSS sound.

jetrexpro

Owner
Charles that is high praise and Electra-print is reasonably priced. You could probably get silver secondaries for not much more than $1000.

jetrexpro

Owner
Grannyring, my Audio Note transformers are the Ultra hi B double C Core copper primary/copper secondary. Their primary impedance is 2.7k not 3k. They do have 4 and 8 ohm secondary taps. They are very coherent and dynamic with lots of depth and texture. My notes above have even more details about them. Of course some of this is because they are matched to my Audio Note speakers. My old Sophia Electric trannies were no slouch but there is more natural synergy with the AN/AN combo. They are pricey at around $3800 from the hi if collective. I didn't buy them. I did some work for a guy that had AN connections and he got them for me.
I don't know how to advise you. Not sure you should splurg on $3800 for these unless you were sure they would be the bomb. There are plenty of great trannies like Magnequest, Electra print, Tamura etc and they might work just as well and cost less.

jetrexpro

Owner
Rob, Agree with Charles that the double C core is an amazing transformer. I might suggest that you contact the AN KITs guys and tell them that you are interested in upgrading transformers for the kit one and ask them how their Triple C Core sound as compared to the AN production double C cores. While you are at it ask if you can upgrade the power supply caps to either Black Gate or to the new AN Kaisei 500v power supply caps. Would be very interesting to find out what capacitors they recommend as a Kit one upgrade. This will be a fun project once it happenes. I had a kit one here for a few weeks and that is what took me down the SET path. Regards Jet

jetrexpro

Owner
Grannyring/Charles/Rob, I spent the better part of this weekend getting to know the Belden interconnects; listening to them on their own and comparing them to the Kondo KSL-LP interconnects that I have been trying. It sounded like the Belden needed some extra time in my main system to fully come alive. By Sunday afternoon it was clear that the Belden IC's are very special cables. There is a presence and weight that draw me into the music. There is an emotional heat that makes the Kondo sound emotionally remote in comparison. I noticed it first when listening to vinyl on Saturday and then today I heard it with CD. I'll need a few more weeks with them to see what is what. At this point I could talk about the sonic differences between the two but that wouldn't get to essence of what these cables are doing.

jetrexpro

Owner
The Belden interconnects now have well over 100 hours of burn in and with a quick listen before breakfast they are sounding very nice with lovely tone. I'll be comparing these to Kondo KSL-LP silver interconnects to see which I prefer. I have been trying the Kondo for several months with an option to buy at a very good price.

jetrexpro

Owner
Salectric, I am surprised by the synergy of these WE16g wires. Like Grannyring; they leave me shaking my head.

Grannyring, one run per pole continues works very well in my smallish room. I can also try two runs using my existing bi-wire configuration by stripping off some more of the insulation and jumping between the two positive and two negative pols.

I am going to re try the Belden IC's over the weekend and will report back. By then they will have over 100 hours in my back room system.

jetrexpro

Owner
Grannyring and Salectric, I am home now and listening just to make sure what I was hearing last night holds true. I am finding that I need only one run per pole (4 per speaker in bi wire) to hear a richness and fully developed bass mids and highs with these WE16g speaker cable. Just to make sure I listened to some rock music that I know very well and the bass is as fully extended as with my AN Lexus. These cables are pretty special. Gorgeous clear mids and highs that allow harmonic complexity that I am not used to hearing. It could also be that my new transformers are further breaking in as well but I am pretty sure the WE wire is mostly responsible-Jet

jetrexpro

Owner
Salectric, Un-terminated. Bare ends. I did solder the amp ends since I had to twist the two wires together to make the bi-wire. The Belden IC's have the Switchcraft RCA connectors that everyone is using. My Audio Note Lexus has huge spades on the amp end and bananas on the speaker end. I have thought many times about removing them since they are probably not helping the sound, but did not since it might hurt their resale value.

jetrexpro

Owner
Charles,
The Western Electric 16 gauge wire sounds really nice. I burned them for 5 days in my 2nd system and have been listening to them for 2 evenings. They have a similar tonality to my Audio Note Lexus speaker cables but sound more direct and cleaner. The Audio Note cables sound softer and diffuse. Soft around the edges. The WE16g more direct-less diffuse at the same time dynamic rich and room filling. So far so good. I am surprised!

The Belden IC only have 24 hours of burnin time so its too early to say much. I gave them a quick listen last night and they need more time. At this stage they did not sound very good.

jetrexpro

Owner
Grannyring, I ordered the Belden Interconnects along with the Western Electric speaker wire. I have been trying Kondo silver interconnects with an option to buy. Seller will give me a very very good deal or I would not even consider them. I'll be able to a/b belden with kondo. That should be very interesting.

Will the Western Electric speaker wire best my beloved Audio Note Lexus??? We'll find out! Regards and thank you again for the info - Jet

jetrexpro

Owner
Joe, It was my pleasure. You are welcome back any time. I am looking forward to another visit to your place to hear the new Elrogs.

Grannyring, thank you. You know the rewards of DIY and thank for your many ideas. Looking forward to trying that Western Electric speaker cable/Belden IC.

Charles, Joe and I were talking about how similar our systems sound. I agree with you that these transformers are a very good investment indeed!

jetrexpro

Owner
I have 100 + hours on these new Audio Note Ultra Hi B Double C Core output transformers so its time for an update.
It is obvious that these transformers were born to work with Audio Note speakers. The 2.7k primary impedance is supposedly ideal for both these speakers and the 300b tube...at least that is according to what Audio Note says.

The musical emotional intentions of the singers and instrumentalists and even the full orchestra are displayed in a way that translates into an emotionally connected and charged moment. It's hard to put this into words, but I find myself spellbound by almost anything I spin on vinyl or CD. When a flute or sax or any instrument is playing a phrase I hear the weight of that phrase and also an increased coherency and detail that is extremely musical. But the operative word I use here is COHERENT.

Over the past few months I optimized the power supply so it is fast clean and nimble, but there is something very coherent and dynamic and fast going on now that is completely new. I think it begins with the lower mids and bass. So very powerful, dynamic and large scale without being bloated or slow. The new speed and coherency is creating this musicality. These transformers seem to have extended the reach of the extreme low bass reminding me on occasion of subwoofer territory. The music seems to ride atop the bass and lower mids in a musical way that it did not before. This gives every instrument and voice an added presence and gravitas. Orchestral climaxes are scary events now-So fast and coherent and large scale I am afraid I will get a knock on my door from a neighbor. The large dynamic swings, the push pull from the quiet to loud is completely transformed into a musical emotional event. I am simply shocked at the dynamic range of these transformers.

It has taken a full 100 hours for the mid range to start developing the depth and nuance of the Sophia Electric transformers. The delicate nature of the Sophia's is beautiful and very musical in its own right. The Audio note transformers are starting to display that inner midrange beauty that I had come to expect and was missing. At about the 75 hour point that midrange started to slowly come alive. I am guessing I am in for a treat over the coming weeks as these trannies further developed. From what I hear they need well over 200 hours.

jetrexpro

Owner
System edited: Installed Audio Note Ultra Hi B output transformers today. They will take a few weeks to come around. Put on some big orchestral music just to see how they sound right off the bat. The bass is very powerful and controlled. I also heard some very interesting depth and texture. They sound like they have a cold and will probably sound like this for a days.

jetrexpro

Owner
Bill - Charles is right!! LOL! What coupling caps did the Jupiters replace?
I am curious about how these new Audio Note power supply caps would compare to your Clarity Polypropylene caps. I shouldn't be so quick to do a blanket dismissal of Polypropylene since I have only tried Wima.

jetrexpro

Owner
Grannyring and all interested DIYers,

The Audio Note Kaisei 50uf caps have been in my amp for two weeks and have about 100 hours on them and their sound has settled so it is no longer changing. All that I said above holds true. They have a purity and clairty that no other cap I have tried in my power supply has. I have tried oils, polypropylene, polypropylene with bypass. The Audio Note guys know the Black Gate sound and I believe they have worked on these caps so they sound like Black Gates. An open and very free sound. They don't have much of a sonic signature, they just somehow allow a clarity and purity to shine thru. Because I dont detect a sonic signature I feel confident in ordering more to replace the remaining oils my amp's power supply. Regards-Jet

jetrexpro

Owner
Grannyring, Tuesday night - the very pure open and crystal clear sound of the AN Kaisei caps has returned.

I am shocked at how much influence the capacitor in the C2 position has over the sound of the amp. Much more than any other passive component in this amp. More than changing the Vcap coupling cap to Duelund. That tells me the design of an amp or pre amp must begin with the power supply. Parts choices here are perhaps the most critical part of the whole amp and not by a small margin -Jet

jetrexpro

Owner
...and now tonight the AN Kaisei caps have turned dark and a bit grainy. They sound like oil caps. I spoke too soon. No fun :(

jetrexpro

Owner
Grannyring,

You can see the picture of the Audio Note Kaisei in my pictures above:DIY WE91a Power Supply pic

The Audio Note Kaisei 50uf/500v capacitors are taking at least 60 hours playing time to finally stop changing their sonic characteristics. One thing I noticed right off the bat was how clean pure and free of grain these caps are. On Day 3 their hi frequencies were crystal clear and pure. Over the next several days the Midrange follow suit. It has taken the full 50-60 hours for the lows to finally catch up with the highs and mids. Now that the capacitors have reached this point I need to wait a few more days to see if they will develop or change any more from where they are now. Keep in mind that my power supply has three caps so the single Kaisei is surrounded by an oil on either side. I will most likely place an order for the additional AN Kaisei caps to finish out my supply. If I feel that I have too much of their sonic signature I can add an oil back in.

At this point I can say that I like Kaisei better than the Wima Poly caps bypassed by film caps. The Wima/bypass stack added richness but also added grain and mud. I was never totally convinced by them. They added color and texture in a way that did not work for me in my system and I alway felt like I heard the plastic in the polys. I am not totally going to dismiss this bypass technique since there are many ways to do this and I only tried one way so someone with more patience and experience may have better results.

At this stage I think that Oil caps sound smooth and rich but lack the crystal clear purity of the Audio Note Kaisei. Kaisei have that richness and musicality while at the same time not adding extra noise and grain. Vintage parts like oil caps and Allen Bradley resistors get the music very much right but can in some situations add some noise.

I am surprised by how much influence this cap has in my amp and I also am learning a great deal from this power supply journey that started 3 months ago. I don't know how much playing time the AN Kaisei cap need to be fully broken in so I'll keep you posted -Jet

jetrexpro

Owner
Grannyring,

I have installed new production 50uf/500v Audio Note Kaisei capacitors in the C2 position in my power supply. These have been burning in for a few days at 70v so should be partially broken in.
My previous Wima caps bypassed with four film caps sound big, rich and fast, but they take up a lot of room. Let's see how a single Audio Note cap performs. More in a few days - Jet

jetrexpro

Owner
Grannyring, I was just now reading about your Ultra Fi Monaco 845 SET and it probably sounds so good I wonder how much is to be gained by changing the PS Caps. Have you contacted Larry Moore to ask him what he would recommend?
As far as bypass bundles go, I think you could start with a smaller first value, like .0010 and then work up from there.

jetrexpro

Owner
Your math for the bypass sounds very similar to what I am doing. I was instructed to bypass every cap in the PS and every cathode in the audio circuit with this combination of four caps. I have chosen to try this only on C2. I am too lazy and dont want to shell out the $$ for all of those caps to try it elsewhere. I also dont have the space in my amp.

jetrexpro

Owner
Grannyring, My AA friend asked me to honor his request not to share the bundle values. He suggested that you read as much amp design info by Dennis Fraker of Serious Stereo that you can get your hands on. Lots of info about his amp design philosophy online. Thorsten's bundle values should work very well. Thorsten is well respected.

I can tell you that for my system and ears, there is something good about these bypass caps. I was skeptical at first but after several weeks with three of them and six days with all four I like what I am hearing. I think one needs to install all four to get the full impact. Once they have been in for a few more weeks, I'll report back. The Audio Note caps will be here by Tuesday. I'll have to try them at some point but at this moment, I am less motivated. -Jet

jetrexpro

Owner
Grannyring, my AA Tube DIY friend had asked me not divulge the bundle values, but I emailed him to ask his permission to share. Thorsten Loesch's Legacy 300b amp uses Ansar Supersound Polypropylen Capcitors extensively used throughout the Amplifier and his bundle choices are here. This is from the website:

"All capacitors feature the complete recommended bypassing with 3600pF ERO KP1832, 2700pF NFS Styrofoam and a further 2200pF Silver Mica unit. Larger Value capacitors have a further ERO KP1832 0.075uF 800V bypass capacitors."

jetrexpro

Owner
I uploaded a picture of one channel of the WE91a power supply if any of you are interested in seeing the red Wima cap surrounded by the four bypass caps, LOL!

"DIY WE91a Power Supply pic"

Not enough space to make these additions neat and clean. It would have to sound really amazing for me to want to figure out a way to use these long term.

jetrexpro

Owner
Grannyring, The Audio Note electrolytic caps should arrive very soon and I'll report back in a few weeks or so on their sound. I'll live with the polys bypassed by film caps for a while first. Actually polys bypassed by film caps are sounding pretty good so far :) All these caps take up an a lot of space and some time to settle in before there sound stops changing.

jetrexpro

Owner
Charles, The Coincident guys probably did all the trial and errors years ago that I am doing now and they have an amp that most think is one of the top 300b amps around. I'm in a learning phase mostly about power supplies at this time. Before giving up on polypropylene caps I am in the processing of bypassing them with film caps. Although it makes me wonder what my amp wound sound like if I started with polyprops in the PS and then voiced the circuit around those. They are very fast hi bandwidth caps.

Dan, Thank you for the tip about terminating the shield at the power source. Much appreciated!

jetrexpro

Owner
Charles, I've seen many many amps and preamps including yours that use polypropylene caps so it is distressing that I don't favor their sound (at least in this application). Yes sometimes its fun but it can be distressing when my ears tell me something that goes against the standard HI FI cannon. And some of this may be because my Audio Note Speakers sound a certain way and I may simply find that the more Black Gate caps I use in this amp the better it sounds with Audio Note Speakers. After all the hi end Audio Note amps are filled with Black Gates and so far everytime I put a BG cap in my amp I like the sound better than before.

I am guessing that most polypropylene caps would sound better than most any standard electrolytic cap. Most builders of hi end gear shun electrolytic caps but Black Gate caps are not your standard electrolytic. BG's contain graphite. I am hoping that the Audio Note caps sound close to how BG's sound or I can go back to the oils.

jetrexpro

Owner
Charles, The control over dynamics, coherence and the ebb and flow of especially large scale orchestral music is impressive. It seems to turn on a dime to handle loud and soft passages with a sudden response. It does make the music more expressive. I'm kinda shocked at the speed and dynamic expression. Better than the original supply for sure.

On the other hand I am finding that I don't like the sound of Wima Polypropylene Caps in the power supply. When I began this power supply learning experience, I replaced oils in the power supply with these Wima Polypropylene caps. I know many others including Grannyring have had success with Polypropylene caps but they are made of plastic and I find that I hear the plastic in the sound. Oil/Paper caps sound more natural to my ears. I haven't totally given up on Polypropylene but I have ordered the new Audio Note Kaisei Electrolytic Capacitors just in case. They should arrive along with my Audio Note Ultra Hi B output transformers next week.

Oil caps in the power supply sound sweet and smooth to my ears. Warm and friendly and now my amp is missing that sweetness. If the AN Electrolytic caps don't sound sweet I'll go back to oils but will order a 50uf to match the value of the Poly cap. I have some faith in Audio Note since they have relied on the now discontinued Black Gate Caps for years and their new electrolytics are hopefully building upon BG technology. This has been a real journey in which I have learned a lot. It's a real balance trying to get everything to work just right -Jet

jetrexpro

Owner
Salectric, The sound does start off kind of cold for the first hour and then continues to improve over a few hours with these big transformers. On weekends I leave it on for hours at a time and it sounds best like this when everything is fully warmed up.

jetrexpro

Owner
Manga, Thanks for your kind comments. My blow by blow description helps me remember where I started from and all the changes I've made. I use Takman Rex in the circuit of my phono pre in a couple of spots and I agree with your assessment. Organic and natural sounding. I've got a mix of these and AN tants in that circuit. Carbon Comp resistors have a very natural sound. Allen Bradley resistors are Carbon comps as well. They are a great sounding resistor used in a lot of classic gear. Audio Note Tants sound very good to my ears but they are more expensive.

So far I think low DCR contributes to a nimble and fast supply as does other factors the most important being a properly designed supply. A very generous fellow I met on the AA Tube DIY site suggested I change one of the capacitor values in my supply and it greatly contributed to the way this amp handles dynamics, power and speed. After living with this sound for about a month I added over spec Heyboer power transformers.These transformers have a much lower DCR than the transformers they replaced. I also took out the single 10H/155 ohm choke and replaced it with two 2H/9ohm chokes so now the DCR is super low. It all contributes to a nimble supply that is able to supply power very quickly and efficiently to the audio circuit. I've also changed some of the power supply wiring to 12 gauge which should contribute to a more efficient energy transfer.
The amp sounds more powerful and has better control of my speaker's woofers. Dynamics and orchestral tutees are coherent.

But I think the single biggest bang for the buck was changing C2 to 50uf. The Joe Robert's we91a calls for a 15uf at C2 but a 50uf is a nicer value there in my opinion. The power supply settles more quickly and smoothly and sounds that way to.

Manga, are you building your own equipment or modding gear you already have? Are you into low power tube amps?

jetrexpro

Owner
Brett! Thank you. I'm guessing an LP. and based on the last time you stopped by it might be Cassandra Wilson, or The Three, or Paul Desmond. it might also be john McLaughlin. What an amazing guitar concerto he wrote!

So thoughtful Brett!

jetrexpro

Owner
Grannyring Wima is working in Combination with oils in my power supply. But with two Wimas in the PS I started to hear an unnatural high frequency that was hurting my ears. They may work for you they're not too expensive so maybe worth a try. The audio note power supply caps should be very good since they are building upon black gate. But the audio note guys admit they are still not finished with the design. I wish I knew of something I could recommend wholeheartedly.

If I had to make a choice right now I would make sure that the power supply in your new amplifier is designed an optimized correctly so it's fast and efficient and feeds the audio circuit what it needs so it sounds great. If your power supply does have electrolytic's and they don't sound good, I would then try and oil or two just to see what they sound like since they are relatively inexpensive. Although from what you have said they may not fit. I guess I would try the audio note caps if the values that they have would work. At least we know that the audio note guys understand the black gate sound and would not offer a product that they felt was less than that.

jetrexpro

Owner
Grannyring, BG VK caps 22uf 350v. Parts connex has some of those in stock. BG standard 47uf 100v Percy may still have some of those in stock.

jetrexpro

Owner
Got it thanks Grannyring. Used on the B+ and filament supplies. Another power supply cap I want to look into are the new Audio Note caps. They are trying to build upon the discontinued Black Gate caps. The Audio Note guys have been developing them for the past few years. The HiFI collective has them. I am having very good results using Black Gates in the bypass circuits on the driver tube and 300b tube. Very open and natural sounding. Percy audio and Parts Connex still have some BG caps.

jetrexpro

Owner
Grannyring, Great that you have had positive results with Clarity TC cap Polypropylene. Did you use them in the power supply as well as other places or just the power supply? Can you describe the changes? I am guessing you are hearing additional clarity and speed from your Dude pre. They are costly caps but sounds like they are worth it..

I didn't have as good results with my Wima Polypropylene experiment. I replaced both oils in my power supply with Wimas and after two weeks the high frequency was hurting my ears so I pulled the 1st Wima (C1) and replaced it with a GE F97 oil and the hi frequencies came back into balance. I left one Wima in the C2 position. I like the balance of one oil (C1) and one Wima Polypropylene (C2). Combines and silky smooth oil with the speedy Polypropylene. Some folks bypass Polypropylenes with small value film caps.

jetrexpro

Owner
Brett you may be more excited by the AN transformers than me:))

I am very curious to see what a true WE91a (pentode-triode strapped) amp sounds like with AN trannies through AN speakers. Audio Note's amps use 6SN7 triode driver tubes in many of their 300b amps. I guess if I were going to follow the true Audio Note philosophy I would build an amp with 6SN7 triodes. But what usually happens with 6SN7 drivers is you have to make a two stage driver in order to effectively drive the 300b which makes the amp a 3 stage amp.

I want to continue what I have started by making what many would say is the next progression of a modern two stage 91a amp and that is a one stage low impedance pentode driver stage capable of fully driving the 300b output tube. The C3M pentode driver tube is that next progression. A two stage amplifier...Jet

jetrexpro

Owner
Reposting my system update with paragraphs:

Over the past month or so I have been doing some work on the power supply of my Western Electric 91a 300b SET amp. With the help of an Audio Asylum friend I have optimized it so it is faster, lower DCR, and more responsive to the audio circuit's moment to moment power needs. Lower DCR (resistance) came from two new way over spec power transformers by Heyboer. These PT's have a resistance that is over 50% lower than my old Stancor power transformers that I got from ebay when I was first building this amp. We also looked at the values of the capacitors in the PS circuit and made some changes there. The result is an amp that has more control over the woofer which makes the music sound more dynamic and speedy. Rock and orchestral music has more punch.

Grannyring knows about this: I am trying WIMA caps (polypropylene) in the power supply and am not sure I like them more than the oils they replaced. There are some that feel polypropylene has no business being in an audio circuit and other folks bypass them with small value film caps....I plan to try a few bypass caps to see for myself....More on that later.

In a few weeks new output transformers will be arriving. Audio Note Double C-Core Ultra HiB copper output transformers. My current output transformers are Sophia Electric 91-05 and they are beautiful sounding. They work really well in this circuit and they should because the guys at Sophia Electric love the WE91a sound. My current amp is tweaked and sounds really good so the plan is to build a 2nd amp and use these new transformers for that. This new amp is going to be the C3m pentode driving a single 300b output tube. Yes I like the sound of a pentode driving a 300b tube! Very natural tonality, musicality and pacing. Many respected folks use the C3M pentode in various applications. Yamamoto and Shindo to name a few. The C3M pentode has a much larger ability to drive a 300b tube at the same time with lower impedance than the 6C6 pentode. My current amp uses a 6C6 pentode to drive the 300b and it is a wonderful compelling sound.

But before I build the second amp I'll uninstall the Sophias and put the Audio Transformers into service on my present amp. These AN transformers have a 2.7k primary impedance which is specifically designed for use with Audio Note speakers. I've lived with and loved my Sophia output transformers for about 3 years now so I will be able detect the sonic differences between these and the Audio Notes. The cost difference between AN OPTs and Sophia OPTs is quite a lot. They are physically huge too. Mounting them will be a challenge. I'll probably do a temporary mount so when I decide to move forward with the second amp I can easily re install my Sophia's.

jetrexpro

Owner
Sorry that my post didnt come in with the paragraphs that I intended. Makes for some confusing reading :(

Charles yes! I will be able to directly compare the two transfomers in my original amp before I build the 2nd amp

jetrexpro

Owner
System edited: Over the past month or so I have been doing some work on the power supply of my Western Electric 91a 300b SET amp. With the help of an Audio Asylum friend I have optimized it so it is faster, lower DCR, and more responsive to the audio circuit's moment to moment power needs. Lower DCR (resistance) came from two new way over spec power transformers by Heyboer. These PT's have a resistance that is over 50% lower than my old Stancor power transformers that I got from ebay when I was first building this amp. We also looked at the values of the capacitors in the PS circuit and made some changes there. The result is an amp that has more control over the woofer which makes the music sound more dynamic and speedy. Rock and orchestral music has more punch. Grannyring knows about this: I am trying WIMA caps (polypropylene) in the power supply and am not sure I like them more than the oils they replaced. There are some that feel polypropylene has no business being in an audio circuit and other folks bypass them with small value film caps....I plan to try a few bypass caps to see for myself....More on that later. In a few weeks new output transformers will be arriving. Audio Note Double C-Core Ultra HiB copper output transformers. My current output transformers are Sophia Electric 91-05 and they are beautiful sounding. They work really well in this circuit and they should because the guys at Sophia Electric love the WE91a sound. My current amp is tweaked and sounds really good so the plan is to build a 2nd amp and use these new transformers for that. This new amp is going to be the C3m pentode driving a single 300b output tube. Yes I like the sound of a pentode driving a 300b tube! Very natural tonality, musicality and pacing. Many respected folks use the C3M pentode in various applications. Yamamoto and Shindo to name a few. The C3M pentode has a much larger ability to drive a 300b tube at the same time with lower impedance than the 6C6 pentode. My current amp uses a 6C6 pentode to drive the 300b and it is a wonderful compelling sound. But before I build the second amp I'll uninstall the Sophias and put these bad boys into service on my present amp. These AN transformers have a 2.7k primary impedance which is specifically designed for use with Audio Note speakers. I've lived with and loved my Sophia output transformers for about 3 years now so I will be able detect the sonic differences between these and the Audio Notes. The cost difference between AN OPTs and Sophia OPTs is quite a lot. They are physically huge too. Mounting them will be a challenge. I'll probably do a temporary mount so when I decide to move forward with the second amp I can easily re install my Sophia's.

jetrexpro

Owner
Drubin yes, looks like Audio Note removed Indian Rosewood from their choice of finishes. Perhaps it was getting rare and expensive..who knows. I like several of their finish choices, including Apple which is probably my favorite. I bough these speakers used and they seldom come up for sale so I took what I could get-Jet

jetrexpro

Owner
Drubin, the finish on the AN-e'sis indian rosewood

jetrexpro

Owner
I have read that some DIYers actually remove the metal container that house black gate capacitors and they replace it with a wooden dow of appropriate diameter. They drill a hole in the dow and place the cap inside. I believe they seal it with bees wax. Those guys also believe wood is good!

jetrexpro

Owner
I am also struck by the Duelund's abilty to retrieve detail in a singers voice. I am hearing delicate subtle inflections that I simply had not heard before. Beautiful and very expressive. Actually I noticed some of this almost as soon as I installed them.

Charles,
After reading a review in Enjoy the music where the reviewer compares the jupiter copper to the Duelund CAST it does sound like which Cap you choose is a personal choice since they are all very good. What cap did the Jupiter's replace in your Franks? Since you have Duelunds in several positions in your system already, your choice of the Jupiters makes good sense. After all it is the correct mix of parts types that creates the sonic magic of a great sounding system. These top Caps are made with natural materials like paper, bees wax etc. The more I think about sound, using natural building material is important. Building my amp on wood was easier but it was also a choice to build it on a natural material. I am guessing it would sound different if I built it on aluminum or steel.

Bill, I was looking thru your review threads for your thoughts on the Jupiter's. I am curious to know your impressions. Gratified to know you are looking in on my DIY projects!

jetrexpro

Owner
The Duelunds have been in my amp for almost 4 weeks and probably over half of the 400 hours they require to be fully burned in so it is time for a report.

For the first two weeks they sounded ok nothing special. Right from the start I noticed they sounded more natural than the Vcap Teflons. The Teflon have an extra creaminess and musical connective tissue that I very much enjoyed over the past few years. This extra additive juicyness was very addicting and connected me emotionally to the music which of course is very important.

At around 250 hours the Duelunds are much more natural sounding than the V caps but their virtues go way beyond that. There is a richness in the tonal pallet that that is supremely musical. In my system I would not call them neutral. At this stage of the burn in I am struck by the natural detail and the tonal richness. Even the air and space around the instruments seem more natural. It is a neat trick they do by sounding so natural but at the same time displaying such a colorful texture. The most important thing is the emotional connection. For the first few weeks they failed in the emotional connection department and I was ready to put the Vcaps back in. But about a week ago I started to feel the it but now it is an even deeper connection. The combination of natural detail and endless tonal richness is now what is connecting me emotionally with the music. They seem to be ready to respond colorfully, deeply and naturally to what ever music I care to throw at them-Jet

jetrexpro

Owner
I installed the Duelund 0.1uf Copper cast coupling capacitors. Sound nice right off the bat, but they require a long break in period

jetrexpro

Owner
Charles/Brett, I had the choice of the Duelunds, the V-Cap copper and Audio Note coppper. All are both reported to be amazing in different ways. V-cap copper said to be more transparent and revealing. Duelunds said to be warmer more musical emotional connection. AN copper also very very musical. All probably a step up from the VCap Teflon. Lots of great choices out there.

jetrexpro

Owner
System edited: I took possession of two Duelund Copper Cast .1uf caps today. I'll put them on the cap burner to help break them in while I am out of town this week. Plan on putting them in the amp when I return on Saturday 12/13

jetrexpro

Owner
Charles1,
Its also fun to listen to organ music with 300b. THe reverb from the church, if it is recorded well floats thru my listening space and hangs in the air. I've been a fan of organ music since I was a kid going to church every sunday. In NYC we have easy access to some great churches and organs.
Jet

jetrexpro

Owner
Charles, "Striking a chord" is an apt pun :) The magic that comes from a six string guitar may be why so many people gravitate to that instrument. And when that six string instrument is well recorded its no wonder so many hit records feature guitar in one way or another. About a year ago I remember playing a CD of this heavy rock band and the moment the guitars came in the sound was so present and forward reaching it was like I was wearing headphones. It was actually a shocking experience.
A recording of the 6 Bartok String Quartets played by the Emerson String quartet comes to mind. This is a recording I have had for years and while it is great music played by great musicians, I had thought it was a thin, scratchy recording. It had been about 5 years since I played it and had not played it on my present system. About a month ago I put it on and was greeted by a rich and harmonically deep recording that was totally involving. There was still some of the scratchiness, but that was simply how the music was recorded or how the CD was mastered. It was the mid range that was now transparent, deep and rich and made the performance an emotional experience. Thanks Charles.

jetrexpro

Owner
Hi Charles, I texted him today and he is well. I told him you were asking and he might jump in here to say hello. If he is like me, he is enjoying this good weather we are having here in the east. I have been spending a lot of time outdoors before the really humid weather takes over in July and August.

jetrexpro

Owner
I have been enjoying the Tempo Electric Silver 16 gauge speaker cables that Brett sent for about a week. They are very coherent as one might expect. Detail is in sharp focus but it still presents the music as a whole. Very nice! In my system the mids are nicely detailed and painted with a fine brush that allows an amazing amount of detail to shine thru. They are rich sounding without any etch. The sound does not reach into the room and seems to stay within the boundaries of the speaker plane.

My Audio Note Lexus LX 80 strand copper Bi Wire are slightly less coherent. The mids are painted with a broader brush and as such, the detail is less focused. The mids are richer and in my system the sound fills the room in that 3D intoxicating way that I have grown to except. There seems to be some synergy between the AN speakers and the AN cable. Personally I favor the presentation with the AN Lexus speaker cables.

My opinions may have been reached because for two years I have voiced the system with the same interconnects, speaker cables and 2 inch maple table and I have grown accustom to the basic character of my system.

jetrexpro

Owner
Thanks TJ! Hope things are sounding good up your way. This weekend those bad sounding little red PRP resistors are coming out of the my phono pre power supply. Good ridden's!

jetrexpro

Owner
oh you boyz are too much! :)

jetrexpro

Owner
Charles, Agreed, there are many posts about AC and DC heat. I will try DC at some point. Probably not any time soon. I want to get to know the amp and the sound without pots so it will be a few months.

BTW- Dan and Charles, Brett has been kind enough to send his Tempo Electric solid core silver cables. They should be arriving today. I'll install them pretty soon and post my observations.

jetrexpro

Owner
Thanks Grannyring. My projects are a great source of satisfaction as yours surly are. Fun stuff for sure. Best wishes for your push-pull project. Keep us posted.

Charles, It speaks to the build quality of the EML's that they would work without hum pots. And you are right, they are amazing tubes. Muscle and delicacy at the same time and very dynamic. I need to build or buy 5 Volt DC regulators and see for myself which sounds better, AC or DC heat.
Jet

jetrexpro

Owner
I use A/C heat on my 300b filaments which almost always requires hum pots to null the hum. The advantage is that some folks think A/C heat sounds better than DC heat. I don't know since I have not tried DC heat.
Anyway...
Because the EML300bXLS tubes are so well internally balanced, I was able to remove the Hum pots and still use AC heat. Now the 300b bias is going thru the center tap of the 5volt filament transformer. Without the hum pots, the sound is much freer and alive and not by a small margin. I am loving this. A/C heat and no hum pots! Who would have thunk it possible?

jetrexpro

Owner
TJ, The EML's are very impressive indeed. I have owned them for two months now and have gotten to know them. Listening to most everything from ok sounding recordings to great recordings the EMLs bring additional enjoyment. There is a slightly forward nature to them that sucks me into the performance in a way that I have not previously experienced. They produce a sound that kind of reaches out and grabs me. Love the additional instrumental texture they bring in combo with my ANe speakers. My wife digs the sound too which is saying something. Beware of that slight forwardness as it might for some be a bit too much. As you can tell, I happen to enjoy it.
I did not have the WE replica Psvanes and have not heard them. When shopping for higher end 300b's I did read about them but ultimately went for the EML's. My psvanes were the ones with the black coating which I have since sold. My impressions of the comparisons of the EML/Sophia/Psvanes, are further up in my thread.
Regards
Jet

jetrexpro

Owner
Thanks Brett. That little 6C6 tube that is driving the EML300b was probably made during WWII. Pretty amazing fidelity for a 70 year old audio amplification device :)

jetrexpro

Owner
Charles/Brett,
Listening with the EML's over the long MLK weekend and there is a certain organic rightness and power with these tubes. Especially in the lower mids and bass there is an ease and expressiveness that takes the listening to a higher level. I think Dan said it as well, instruments are real.

As much as I like the EML's, I am still very much appreciating the Sophia "mesh" as an alternative. There is a creaminess and velvety texture that is simply fun to listen to with certain types of music. Slightly romantic and soft around the edges with a delicate mid range texture.
Nice to have both.

jetrexpro

Owner
TJ, Both the Sophia and EML Bases are the same. About 1 and 5/16 inches.

jetrexpro

Owner
Nope. This is the first amp I have built. BTW, the folks at Sophia Electric advised that 60mA is where they like this amp to run. I have tried 70mA with my Sophia Mesh and Sophia output transformers and I can confirm that I prefer 60mA.

jetrexpro

Owner
Salectric, Mine is the Joe Roberts. around 425b+ depending in which rectifier. 1100 ohms on the 300b so it runs around 60mA. 6C6 driver with 100v on the screen and 190v on the plate. I like the sound better with C5 the 6C6 cathode bypass removed

jetrexpro

Owner
Markhh2,
I put the Psvanes in a few days ago to let them wake up after a few months of hibernation. Tonight I gave them a serious listen. Even after several weeks with the EML's the Psavne's are very nice. They are not as dynamic and lack the believable sense presence of the EML's but they are capable of very good musicality and have clear bass, mids and hi's. They lack a mid range richness that both the EML's and Sophia's possess. EML's make a more authentic richness that just reaches in my room like nothing I have heard. The Sophia Mesh make a slightly romantic version of that richness and it is quite captivating. A delicate textural thing. Maybe its the way they work with my Sophia 91-05 output transformers.
In my system the Psvanes are more than adequate and very satisfying for their cost. The EMLs are several ranks above the Psvanes. The Sophias are Mesh and there is something very special about mesh. One more thing, the EMLs are vastly superior to both in the way they handle complex orchestra textures.

Mark, If you love your mesh EML I would think the Psvanes would not be for you. But if you might want a less expensive contrast to your mesh, Psvanes might work.

jetrexpro

Owner
Brett, If Charles is smart, and he clearly is, he will kick us hooligans out before he succumbs. Wish I were still 20 and a road trip like this was actually feasible!

jetrexpro

Owner
Hello Markhh2,

We do have similar systems. I can only imagine how good those EML mesh sound. RED Rega is best! I will put the Psvanes in in a few days and report back. I haven't listened to them for a few months.

Regards

jetrexpro

Owner
Ok Brett, if you insist!:) After you get back from the 6000 mile round trip to Dan's place you can make the 25 mile journey to to Brooklyn. Let me know when you go to Dan's I'll go with you. I would love to relish in the sound of his Tannoy's. On the way we can stop at Charles's and get a Coincident education!
I am blown away by how good these EML's are.

jetrexpro

Owner
System edited: Over the Christmas break I bought Emission Labs 300b XLS tubes. They have about 60 hours so far. They bring the instruments into the room in a way that the Sophias Mesh and Psvanes do not which I was surprised by since the Sophia's do a great job of filling my room with music. Instruments and voices are more fleshed out and textured but somehow this happens with a very satisfying clarity and tonal accuracy. They seem to be a bit more dynamic as well. Right now they have a slightly forward nature that has been slowly subsiding as they burn in. With 60 hours I guess they need more time to fully flesh out. I need much more time with them including trying various rectifiers which will supply different B+ voltages. Will report back later.

jetrexpro

Owner
JT, Next time you get down to the city and you have some extra time let me know. Brett, once again it was a pleasure and it would be great to have you back over.

jetrexpro

Owner
Brett,

It was great to meet you and listen to music with you. Thank you for bringing a suitcase full of goodies to play around with and listen to. Charles, we started on vinyl listening to Frank Sinatra "Only the Lonely", Pat Methaney "First Circle" and several other things so Brett could get a sense of my vinyl rig and then moved to CD.

The Sophia RP's were a highlight of our afternoon not to mention Cassandra Wilson! What an amazing haunting voice. The Sophia Royal Princess's made music with greater sonic confidence and emotion than my Psvane's and Sophia Mesh. Not only did Cassandra sound haunting but a very familiar recording of the Ravel Piano Trio in A minor played by the Ahn Trio revealed bowing nuances that contributed to more emotion than I have heard before. I thought I was listening to a different recording. We listened to Miles Davis "Nefertiti" which is one of my favorite Miles recordings which Brett had not heard before. But two hours was not enough time to really get into these tubes so drawing any firm conclusions would be premature. We didn't listen to much heavy duty classical or rock stuff. One thing I did notice that there was more bass power than I am used to and that can be a problem since the E's are already a bit to big for my room. How many people living in NYC would say they would like a larger listening space? Many I would imagine. All in all it was a fun afternoon.

Too bad TJ could not come. We missed him and his Takatsuki's and amps. (Hope he AN cap break in is going ok). That would have been very interesting to hear the Taks in this context. I am also very interested to hear Emmision Labs 300's.

jetrexpro

Owner
Elescher, I sent you my # thru the Agon mail system. We are setting up a get together.

jetrexpro

Owner
TJ, I am out of town today but back early friday. Keep us posted if you can come by. Congradualtions on the AN silver! I sent you my ph# thru the AGON email system

jetrexpro

Owner
Tjkurita, I'll be around this friday mid afternoon into the evening if you are able to by. Isochronism is more than welcome too!

jetrexpro

Owner
I am very interest to hear other SET amps in my listening room as well. As Charles pointed out the different presentations would be educational.

jetrexpro

Owner
Tjkurita, We do have two felines. One is seen sitting on the rug in my system pix. Hope this doesn't affect our plans too much.

jetrexpro

Owner
Isochronism--LOL!

You guys can bring or not any gear you would like. Although I would like to hear those takatsuki 300b's. Hearing Blackie's amp and the Doshi would be a treat, but not a big deal if folks dont want to lug heavy gear.

Tjkurita--I am not an expert on how and why these wonderful music making SET amps work but I can at least pull out the schematics for my amp and phono pre amp and we can go over them. I will answer whatever I can.

Jet

jetrexpro

Owner
I just had a nice conversation with Isochronism and have PM'd Elescher and Tjkurita. Will communicate with all thru email or text once everyone responds. When Tjkurita has the AN silver Caps installed and is ready, we will set something up.

jetrexpro

Owner
Elescher,

You are welcome to bring your Troy. It would serve well if Tjkurita's amp if it is not an integrated.

jetrexpro

Owner
Tjkurita,I sent you a PM thru the Agon system

jetrexpro

Owner
Tjkurita,

Sounds like a plan. Hearing that amp and the Takatsuki's would be a treat.
Keep me posted and we'll set up a date. If Blackie's amp has volume control we are all set. If not you would need to bring your preamp since I dont use one.

jetrexpro

Owner
Tjkurita,

If your plans do get you into NYC this fall let me know. Isochronism and you are welcome separately or together.

Jet

jetrexpro

Owner
Isochronism,

Sounds good. PM me and we can set something up.

jetrexpro

Owner
Tjkurita,

Listening to some samples of Lee Konitz "Motion" on Amazon. Pretty cool indeed. I am starting to dig pianoless small group jazz. Thanks for the recommendation.

jetrexpro

Owner
Isochronism,
"NYCSET" Great name for our audio club. PM me if you want to come by sometime. Would be a pleasure!

Tjkurita,
Roaming member you are! I understand about needing more space. I would like an additional 20 square feet to let my AN-E's breath. Let me know when you are in the city. I am in Park Slope Brooklyn and would enjoy your visit anytime.

jetrexpro

Owner
Charles,
If we were all in NYC it would be quite an audio club. Yes we do seem to share many of the same musical tastes. Lately I have been spinning alot of Chet Baker which is continuing the theme you and Fortapache started in a thread a few weeks ago. "Chet in Paris" the pianist Richard Twardzik plays on a few cuts. His life was cut short by heroin...pitty. As a classical and jazz music listener his approach is pleasing to my ears as he was stretching jazz harmonies into 20th century orchestral.

jetrexpro

Owner
Hi Tjkurita,
Thanks for your kind comments. If you are in NYC you are very welcome to stop by. It would as well be a treat to hear your system make music.

Indeed, DIY is a great way to get a nice bang for the buck. With a SET amp one part change can yield a big difference in sound. Much less expensive than voicing a system with interconnects or speaker cables. I have been voicing my amp with the same equipment stand, speakers, cables etc, which also keeps the variables under control.

I have heard Tubes/Amps, namely the Yamamoto 2A3 amp, which is faster than mine but not as full bodied. I guess folks can take their choice of tube and run with it. Each has its magic. I would truly love to hear the AN-e's with the Yamamoto 2A3 amp. I have a feeling the combo would be pretty amazing especially in my room which is not huge.

jetrexpro

Owner
Phduncanson,

Looking forward to getting together. Always a pleasure!

jetrexpro

Owner
Hi Seikosha

I had never thought about it but I see what you mean by the Steempunk reference. I did want do show the inner workings of the amp (I have covered the high voltage section with glass plate). It lets visitors see how the amp actually works. It also makes changing parts (voicing the amp) very easy.

jetrexpro

Owner
System edited: After adding Audio Note Tantalum resistors and replacing the four Solen caps directly in the signal path with two Vcap TFTF's and two Audio Note Copper caps and living with the phono pre over the past two weeks I can report a more open and beautiful sounding vinyl rig (before installing the caps I pre burned them on my cap burner for two weeks). I suspect it has surpassed my Rega TT in its ultimate potential. Last night I had a few friends over and we listened to about an hour of vinyl and then switched to CD and the difference in room filling musicality was dramatic. Not even close. Many comments from the assembled group. There is a living and breathing texture with vinyl that is missing from my CD rig. The Solen Caps and Allen Bradley resistors are very good and plenty musical and keep the cost down for an inexpensive DIY project, but the Tants and higher end caps make listening even more compelling.

jetrexpro

Owner
We have two kitties as well and yes it is clear that they are running the show :)

They are also good listeners--sitting very quietly in a "cat trance" for long periods when there is pleasing music playing.

jetrexpro

Owner
Albert,

That's a purrin made product.LOL!

jetrexpro

Owner
Thanks Emailists. I had not built audio gear previously. I did have solder experience and could read a schematic. I had a ton of help from a friend with whom I exchanged probably 500 emails when I had specific questions. The Tube DYI Audio Asylum site was also very helpful. Many of my questions were about parts selections which my system page sites the blow by blow going from mostly oil caps to other types. My second build was the Audio Note (homebrew) Phono Pre and was MUCH easier after building the 91A.

PM me if you are ever in Park Slope you are welcome to stop by.

jetrexpro

Owner
Salectric, It was fun to take the amp slowly from all oils and A-B's in the circuit to where it is now. A good education. I documented it so I would remember what I did and how each part changed the sound.

jetrexpro

Owner
Salectric,
Just make sure to ground the DC filament regulator to earth. I built the M2 Power Supply since I had so many of those parts laying around, but if you have access the M3 thru M8 PS schematic, I would go that route. From what I hear, it is quieter and has better bass. If you don't have access to this email me personally.

Virtually no hum or noise and even less if you build the phono circuit on a separate chassis which I plan to do.

I dont have a great phono stage to compare it to, but even after one week of burnin time, and no fancy tants or AN caps, it easily betters a no name tube pre I got on e-auction a few years ago. Sweet highs and resolving mids. I get why so many folk listen to vinyl only.

jetrexpro

Owner
System Edited--

Built a home brew version of an Audio Note Phono Pre using the M3 Schematic for the Phono circuit and the M2 power supply schematic. Built mostly from parts I had laying around the house. Once it settles in I will start to populate it with nicer caps and resistors.

jetrexpro

Owner
Pulled C-5 from the amp and didnt replace. In this case less is more. Added clarity and detail but decreased gain.

jetrexpro

Owner
7/12- pulled 24 gauge silver hookup wire and installed 16 gauge pure copper.

jetrexpro

Owner
Good point Peter. I have a guard that covers the high voltage section. Took it off to take pictures

jetrexpro

Owner
Thank you Jsujo.

Am still experimenting with different types of hookup wire: copper vs silver and different thicknesses

The Rega TT is musical. The Exact Cart lacks a bit of sparkle in the top end so I pulled the third screw and moved it out about 1/8 inch and the sound has opened up.

jetrexpro

Owner
6/12- finished new chassis

jetrexpro

Owner
5-1-12:

I have been trying 5AR4(GZ34) rectifiers in place of my GZ37s. B+ goes up 20 volts and the sound becomes more confidnet and powerful. The amp jumps to attention with additional dynamics. The downside is the amp sounds a bit more mechanical. Less groovey. The GZ37s lets the amp relax and breathe the way real musicians breathe.

Bottom line--I will keep both GZ34s and GZ37s...why not!

jetrexpro

Owner
Charles1dad,

I was reading about your Coincident 300b. That must be one good sounding amp. Transformer coupled I think and the 6EM7 is an ambitious choice as a driver tube and must have great sonic rewards.

I chose the 6C6 as the driver tube. Tube rectification using GZ37s I had stashed for another project. The Joe Roberts 91a schematic calls for GZ34 rectifiers. Plan on trying GZ34 variants to learn if there are sonic differences. I used 26 gauge pure silver wire for the female RCA jacks/attenuator/6C6 assembly and designed the layout so the inputs are two inches away from the attenuator so a minimum amount of wire was needed. The rest of the amp is a combination of copper and even some stranded wire. In the Sound Practices article by Allen Wright "Tube Preamp Cook book", he talks about advantages using extremely thin hookup silver wire. The Thinner the better. Another article about building a tube phono pre mentions using a bit of stranded wire which the writer claims adds some "air" to the sound. While in breadboard stage I am experimenting with hookup wire.

Tried a Sprague electrolytic cap in the 6C6 cathode position and liked it until I got the Goldpoint attenuator and after two weeks of letting the Goldpoint settle in pulled the electrolytic and put the oil cap back in. The Goldpoints' added transparency exposed the grain and excessive etch that the Sprague electrolytic possessed. I really did not expect to like oils in positions other than the power supply but so far other than the V-Cap in the coupling position oils are working at least for me.

And yes this amp plays all music. Mostly a classical listener, I also listen to a fair amount of rock music and am digging the way this amp handles drums and of course vocals. Peter Gabriel "So" has never grooved so hard.

jetrexpro

Owner
In late Janurary I returned the borrowed Audio Note Transformers and bought Sophia Electric 91-05 Output transformers and Sophia Princess mesh plate 300b tubes. After a month with the Sophia 91-05 OPTs and the Sophia Princess Mesh Plate 300b tubes its time for an update.

The trannys clearly needed at least 300-400 hours to start strutting their stuff. Bare in mind that some other parts like the Vcaps and the 300b tubes themselves could have all finally broken in.

The sound is VERY involving and transparent. Just plain fun to listen to. The sound stage is holographic and if I am not paying attention it can startle me with the full blown technicolor sound pallet at its disposal. This rich tapestry does not come at the expense of speed and transparency. As I mentioned above, the amp continues to be very speedy, fast, like a sports car, but can play heavy and thick just as convincingly. To have such richness and transparency at the same time amazes me.

Seems like this amp really likes the Audio Note An-E's Anyone thinking about pairing the 91a with Audio Note speakers and Sophia tubes and trannies should not hesitate.

My friend and I went to an audio shop to hear some excellent amps and speakers. We left the store and I was very impressed. He turned and unprompted said "I like your rig better: It breathes".

When I got home and turned my rig on and listened, I realized what he was talking about: this rig; speakers amp and all really does breathe. Just such a natural sound.

jetrexpro

Owner
It is built from scratch and I had help from a friend who is an experienced builder or I could not have done it. Also helpful that in Brooklyn NY there is Leeds Radio where I was able to source many vintage parts. There is not an electrolytic cap in it and it has AC heat on the filaments. 2 elements which you will probably not find on manufactured amps for practical reasons. It took two weeks to build.

I installed an Alps volume control directly on the amp to avoid a preamp (for now). It is helpful that the Ayon CD player has a 5V output switch which seems to drive amp nicely.

Charles1dad,
The amp does have a very natural organic sound and it is very fast. Its pacing somehow reminds me of some of the shindo amps I have heard. It is very groovy and swingy. Apparently the WE91A 300b design is known for these attributes. One would think that using all these vintage parts would yield a euphonic sound, but this is not the case. Crystal clear. It plays large scale classical as easily as Jazz.

Room is 20x11. Set up along the long wall.

jetrexpro