|Date: Jan 22 1997 / Paul Wong
Steve, I read a lot of rave reports/reviews of how magical tube amplifier can be especially single-ended triode tube amp. While surfing the internet, I came across Steve's web site about his Zen amp R&D process. After reading his development log, I was sold and decided to order a Zen amp to try it out myself.
My current system is a mid-fi system at best: Onkyo 727, JVC CD player (8-year old), and B&W 602 loudspeakers. Realizing my speakers are quite efficient (90db spl at 2.83V, 1m), I had high expectation of the Zen amp although most people that I talked to were teasing me about ordering a flea-power tube amplifier. After consulting Steve, I put down my money and anxiously waited for my amp to arrive before Christmas (1997). After 3+ weeks, my expectation was building and building (not fair to the amplifier since my high expectation may be just hallucination).
When I received the amp, I quickly hooked it up without even giving the Zen amp a proper home. It was sitting next to my equipment rack on the floor behind my big screen TV. I used a pair of cheap, long interconnects and hooked it up to my Onkyo 727 pre-out. With no proper warm up, I played Kitaro Tenku (very nicely produced, highly synthesized but with the wrong system, the music induced fatigue soon). First, I found the sound anemic. But after adjusting the gain knob on the Zen amp and my Onkyo volume level, the music came alive. I remembered telling myself "I may be self-assuring this amp is doing something but in reality it is not." As the music played on, the Zen amp was further warmed up. I started hearing a 3-dimensional sound stage as Steve described it. My Onkyo produced a 2-D sound stage quite nicely and good imaging. The Zen amp certainly has transformed this into a nice 3-D sound stage.
I can hear all the instruments now and I am hearing the music in a whole new way. The undenying digital/solid state amp analytical, thin, and bright (the reason I picked B&W is its warmth and it helps) characteristics were gone. I can listen to my favorite music without early fatigue. I invited friends over to do an A/B blind test and all correctly picked the Zen amp over the Onkyo. They all commented that the mids and highs are much clearer and instruments could be heard distinctly.
Now, you might say enough of this. Nothing is perfect. How about weaknesses? I talked to Steve and my only complain is Dynamics. I found some numbers lack dynamics. Steve pointed out that may be my interconnects. Remember my cheap, long (5 ft) interconnects between my Onkyo pre-out and the Zen amp. (shreak! -editor)I invited the Zen amp to its new home on my equipment rack and replaced the interconnects with Tara Labs Quantum 66 (not top notch interconnects but certainly a big jump compared to my free interconnects that comes with my satellite dish). I had my doubts about interconnects myths of transforming an OK sounding system to a higher level. Now, I have to admit that it does play a major role in improving performance. Even before the cable is break-in (another myth), the good smooth sound of the Zen amp is again transformed. I would describe this as lifting the silhouette. Although I found the music a little bright the dynamics is back. If the myth about burn-in/break-in is true, the brightness would eventually disappear?! Anyhow, I've tried connecting my CD player directly to the Zen amp and not liking how I hear. I am going to try again with the new interconnects and see if it makes a difference. Also, I am amazed how the sound stage and characteristics could change by simply swapping in another brand of tubes. I also tried the pentode mode and not impressed by it. It sounded bright and forward. The images are literally extended 2 feet. Again, this is with my old cheap interconnects.
Last of all, I would like to congratulate Steve on what he accomplished with this Zen amp design. I am sure I have not yet heard the full potential of what my Zen amp can give me but I believe I know I'll enjoy her company for a long, long time.
Thanks, Steve. Regards, Paul Wong