Description

I have started building this system 5 years ago. My first goals were big tight bass and great mids. I love vocals and chords. I mostly listen to Rock. Grateful Dead, Van Morrison, Traffic, Zepellin, Yes, Genesis, Floyd, CSNY, King Crimson, Neil Young, Zappa, PFM, Le orme,..etc.

I love also spanish music, Mecano, Miguel Bose, El ultimo de la fila.

And finally a lot of female vocals, joni mitchell, natalie merchant, carole king, etc.

I have been changing speakers and amplifiers like 3 or 4 times.

I started with a Rotel integrated, then to a Plinius 8100 and then to the CJ MV50 but with a Modsquad preamplifier.

Finally arrived the SFL-1, which BTW sound incredibly good with the upgrades from Parts Connection. Without the mods it had some veil over the spectrum.

As for speakers, I started with a pair of PSB Mini Stratus, then moved to a Triangle Celius ES and now the Tylos.

At that time, I loved the big and warm sound of the Mv50 but I was after more detail and tonal balance because the voices were almost all the music, way bigs and the rest of the instruments were not so present. So, I love it but I wanted to changed it for good.

I wanted to take the mid CJ magic way beyond.

... that was how the mod journey began.

I wanted above all natural voices with a lot of detail and low bass extension.

Following Jeffrey Behr great advices ,it begun as a simple replacement of coupling caps and minor changes, 0,22 sonicaps platinum instead of the CJ styrenes in order to improve the sound.

But in the end, we changed the whole power supply capacitors and bypasses with Solens and Mundorfs Supremes, almost all the resistors with caddock, rikkens and tantalums, the signal path was rewired with silver wire, the rca chassis connectors were replaced with WBTs, the original binding post were also replaced with edison music post, and the diodes were replaced with fast recovery diodes.

Also, we did put some new ceramic tube sockets and an ac inlet to be able to exchange power cords.

We damped the caps and some chassis parts with ear damping material.

Then, we reconfigured the circuit to eliminate the cathode follower.

After all these mods, the unit was sounding really acurate, with a lot of detail, great mid-highs but a little on your face. The mids were there but without the mid magic CJ always perform, they were cold.

So, after almost 500 hours, the sound was more analytical than warm or envolving but with spectacular detail. And the mids-highs were too agressive.

Then, me a my amplifier designer friend,Carlos Cisneros,(taking advice from Mike Samra) decided to change the coupling caps(the sonicaps platinums) for a set of russian pios military surplus.

Well, at this stage and after 30 hours of caps break in, the amp started to sound wonderful.

It had a very detail sound, great soundstage, great tonal balance and the magic was starting to appear again. The mids were becoming very natural as the break in advanced. The tonal balance was improving.

Then, we decided to put in the second stage of the power supply 2 CSC run in oil caps 100uf each. We had to use a off board MDF to attach them to the chassis.

We keep the Solens in the first stage.

Well, with this caps the sound was way better. When the Solens were alone the bass was very dry, way too tight not real.

After the run in oils came in the sound was full again, bass was tight but with air not dry and the mids body was recovered.

A week ago as a final mod we wired the unit in triode and now Im in my first audio nirvana.

I just wanted to share all this long and strange trip.

Now, I will enjoy my cds for a while. My next plans are upgrade the Rotel with a Superclock and his own power supply. Then, build a passive TVC using the TX-102 S&B and then put a subwoofer.

Any advice will be great.
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Components Toggle details

    • Rotel RCD-991
    Rotel RCD991E, Im using it only as a transport
    • Sonic Frontiers SFL-1 sig
    Upgraded by parts conneXion
    • Tyler Acoustics Taylo Ref Monitor
    These babies are really something.
    • Conrad Johnson MV-50
    Very sweet and airy sounding power.
    • Vibrapods Vibrapods
    Vibrapods and Vibracones in CDplayer,pre and Dac.
    • Gamma Cable Isolators
    Industrial Cable isolators. Ceramic dark brown big ones. Add Focus and a dead background.
    • Bob Danielak 45 Danielak SET
    45 SET amplifier built by Bob Danielak. it uses 45 EML mesh plates. Only puts out 1.5 watts. This picture was taken during the building process.

Comments 15

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Do you have contact information of Jeffrey Behr who does your mods? I would like to do mods to my amplifier.

samuellaudio