Lon E. Armstrong - Lon.Armstrong@gsc.state.tx.us

Knowing the way my life USUALLY goes, I was actually surprised to find the much anticipated Zen amp waiting on my doorstep as I came home Friday evening, on the eve of a three day weekend. . . .I expected I would receive it today, Tuesday, after grumbling at having a long weekend to wait. . . .

But there it was, and it was quickly unwrapped, plugged in and warming up. After thirty impatient moments I dared to run a disc through, one that I have known well for many years, Jimi's "Electric Ladyland." As the first notes of "Long Hot Summer Night" ran out of the speakers, I was pleased and relieved. Pleased because it sounded so good, like I knew it would, and relieved because there was plenty of juice to drive my speakers, thus wiping out my biggest worry of the last month or so. . . .

I was surprised by your tube choices, the "regular" Sovtek EL84s and a Phillips 12AT7 tube. My experience with the cheaper Sovtek tubes was that they sounded "hard" and indeed I found them to have a lower treble glare that became irritating. This dissipated a bit with use, but has not yet completely disappeared.

The li'l Zen saw a lot of use over the last three days. I was surprised in a way at how very much like my old EICO amp it sounded. The push-pull EICO uses 12AU7As and 12AX7As to drive its EL84s, rectified by EZ81s, and this no doubt accounts for the similarity of sound. The only other single-ended amplifiers I have heard used the huge 300B tubes, and had a thicker, richer sound. The Zen was quick and gutsy, with a bright detailed presentation, even in triode mode. My Tara Lab Reference interconnects and Space and Time Phase II speaker wire tend towards brightness, and the combination was a bit much. I swapped these for the only other quality cables I had around, Monster Cables that were considerable less expensive, and indeed the sound took on darker tones, but the lack of transparency and inner dynamics was both very apparent and very hard to overlook. Back went the Tara Labs. . . and the tube swapping began.

On hand I had two Mullard 12AU7As, two Sovtek 12AX7As, two Mullard 12AX7As, and an unbranded 12AU7A from MCM Electronics. I also had a quartet of seasoned regular Sovteks, and a quartet of Sovtek EL84Ms, military spec. tubes. These had sounded very smooth and liquid in my EICO, and indeed, they brought to the Zen a richer, warmer sound, especially when paired with the Mullard 12AU7As. Gone was the treble glare, but gone also was a modicum of dynamics and detail. After many combinations I settled for a while on the amp as you had sent it with the substitution of my very broken in regular Sovteks, and then finally last night returned to the Sovteks that you had sent, intending to trust your evaluation of the performance it offered, and t0 hope that the glare relents. It has a little. It may go away altogether; time will tell.

I wish I had a different set of rectifiers or two to play around with, as in my old EICO even replacing rectifier tubes had a large effect, contrary to the prevailing "wisdom." My guess is that in the Zen as well a little rectifier swapping would be advantageous; I'll probably look for some good alternative brands and experiment.

The whole point is to listen to music, and I did listen, to a variety of music. Jazz is my first love, and lately I have been really focusing on music from the 'Twenties to the 'Forties, from both black and white bands. The Zen, as I suspected, really performed phenomenally well in deciphering the music mastered onto cds from old 78s and metal parts. I was able to hear many nuances of horn ensembles and farther into the rhythm sections than I usually have on other components in my home. Ellington's world of color and drive was presented with all its magic. Louis Armstrong was portrayed with strength and power. Paul Whiteman's "symphonic jazz" swung in its ponderous way, sounding very full and alive.

More modern recordings were also well served. Coltrane's recently re-mastered Impulse Records recordings sounded very clear, crisp and energetic. Miles and his band play their butts off on "The Complete Recordings of the Miles Davis Quintet at the Plugged Nickel," and every twist of the engineers' knobs while recording these nightclub performances was apparent, and even jarring. Keith Jarrett's solo piano filled my room with resonance and melody. I found myself switching the light off often and drifting wherever my favorite musicians wished to take me. I was very easily lost in the music and for the most part relaxed. I did still think analytically about the "sound" and what I could do to "tweak it more; I may never stop being a neurotic audiophile, as much as I would really like to. Give me several million dollars and a few years of free time and I might finally. . . and I might not!

Pentode mode is very interesting: very gutsy and even more detailed, fast and furious. There was actually more bass there than I had expected from your comments, Steve, although a little thinner than I would like as a steady diet. (Triode mode too I found surprisingly to be lacking bass; all of this may be the fault of the interconnects, although I am hard pressed to imagine myself parting with them as they give so freely detail and drive. . . .) Works with large ensembles or full orchestras really sing with the pentode mode activated, as well as (surprisingly?) Janos Starker's solo cello pieces. I will be exploring the pentode mode more in the weeks to come.

Bottom line: I think I will be keeping this little devil in my main stereo. It works fine being driven directly by my Harmon-Kardon cd player, and after several more weeks of tweaking, okay months of tweaking, okay, maybe years of tweaking, I will have made it sound exactly as I wish. Its simple construction yields true audio beauty. I was very impressed at the quality of the binding posts, input jacks, gain knob, transformers and tube sockets. This is a very fairly priced product, and a veritable monster of a bang for the buck when factoring in the sound quality. There is more volume available than I need even in triode mode. I was impressed with its ability to travel from very soft delicately played passages to blasts of notes pounded plentifully. It is the finest sounding amplifier I have ever had the pleasure to own, and its reasonable price has made it possible for me to enjoy Class A sound in my home at last. The downside is that I will now have to consider purchasing a really nice preamp, a better player, better and more interconnects, great line treatment, perhaps better speakers, a nice equipment table. . . .

I am considering writing a full-blown review of the Zen and sending it in to Stereophile magazine. They have published three letters of mine over the last years, and a portion of a record review that I wrote was quoted by their music editor Robert Baird in his April '97 "Aural Robert" column. I would enjoy writing a "real world" review, and I think there is a chance that it would see print at least in part, and I believe that your product deserves the exposure. Keep up the good work Steve! I'll keep in touch with you and let you know my reactions to the improving sound that I anticipate as I listen more and longer to the amp.

And hey: what was that "upgrade" you cryptically referred to? I'm dying to know!

P. S. If you have not yet discovered it, MCM Electronics has KILLER prices on Sovtek tubes, and appears to carry the complete line. . . .



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