I have Don's preamp and got a chance to compare his KT88 tube amp to my McCormack DNA .05 (Platinum Version) amp last week in an extensive listening session with my Spatial Audio M4 Triode Master open baffle speakers. Personally, I hasten to say that the upgraded McCormack is easily the finest amp I have ever heard among the dozen or so I have had over the past 20 years, which include several CJ amps, Modwright, upgraded HK C-II and C-V, Moscode, Plinius, several class-D amps (forget about them!) and a few other decent amps that I now forget that I owned.
I have talked to Don a lot about his amp and have thought that in comparison to a potent SS such as the McCormack, it would suffer in the control of the LF response.
Well, I am delighted to say that the KT88 amp suffers not a bit in the LF response compared to the much more powerful McCormack, which was completely unexpected. And the HF was as brilliant as with the McCormack. The most notable sonic aspect of your amp was the fleshed-out spaciousness of the vocals and instruments, a dimensionality of the sound that clearly exceeded that of the McCormack.
Don did the full-monty upgrades on my HK CII and CV amps years ago and so far as much recollection allows, his production KT88 is vastly better. The amp appears on my volume pot (I have Don's preamp) to have the same SPL at 9:00 as does my McCormack amp, which totally surprised me. It is a very potent amp, but then my speakers present a 12 ohm load so they are easy to drive with a tube amp.
As lovely as the McCormack clearly is, it frankly sounds rather two-dimensional in comparison to the KT88 amp. Yeah, you buy a tube amp to get that luscious 3-D sound with a roundness to the instruments playing, and the inviting mid-range, and I find, which surprised me, a firm control of the LF response with the KT88 that blew me away -- I have never heard that sonic attribute with any tube amp. It has all the control of a SS amp, but a vastly better holographic presentation of the music. Perhaps it is cliche to say it, but it sounds so completely analogue in its performance with all the speed and accuracy of a SS amp. I was enthralled with it in my system.
