Sorry, Sean Casper 421A SET. Although I've since sold it. It sounded good but didn't quite do it for me.
I replaced the 421A with the Transcendent Sound Mini Beast, which seems to have the right virtues for me. Not likely my last or only amplifier, but I remain quite happy with it after 4 months and I'm not sure if there are many better values out there if your speakers are sufficiently sensitive and easy to drive like the Zu offerings.
The Mini Beast outputs 4 watts into an 8 ohm load, but an estimated 7 watts into the 16 ohm Zu Superfly speakers. The 7 watts with this OTL seem to be plenty. People have said the Zu speakers need more like 25-30 watts, but the Mini Beast has been keeping up just fine -- it's all there. Bass response, high frequency extension, speed, tonal beauty.
I had a TRL Dude preamp in the system for all of one week. It was terrific, could very well have been my last preamp, but it didn't meet WAF. When you look at the pictures online of the Dude, it looks quite small. But none of the pictures I've seen had any clues regarding it's actual size -- there were no reference comparisons to hint at scale. You know, it's quite large, unusually large. 19" by 17" by 8". I know a few inches here and there you'd think wouldn't make a difference, but it does! This is a preamplifier built for Andre the Giant. Everything else looked puny by comparison and that just didn't meet WAF. First time she has objected to anything, so I conceded the point to her.
The Modwright LS-100 is not as good as the TRL Dude, but it's quite good all the same, and will tie me over for awhile. I wasn't looking to have a remote control, but the LS-100 has one, and it is actually surprising to me how much I enjoy having a remote control again.
