A good friend of mine graciously sent me this amp on loan to try out, who also wrote a very in depth and detailed review on it here on AudioReview.ca some time ago (check out http://www.audioreview.ca/default.aspx?pagename=review&reviewID=53).
Since Jan's review was very favourable, I was very interested and excited to receive this amp and give it a listen in my own music room. The one caveat here that you will have to keep in mind as you read this is that I do not have the "proper" speakers currently to really experience the full effect of this amp.
At only 2 watts per channel, you are obviously going to need very sensitive speakers. The manufacturer (Decware) recommends at least 90 db sensitivity for the Zen amp. My B&W CM5, at only 88 db are not the best match.
But, as I find often in life, things that on paper, that are not supposed to work, sometimes do. I've used a 10 watt SET amp to great effect on my Totem Sttafs. I've driven Totem Mani-2 (quite possibly the hardest speakers to drive in the universe) with a woefully underpowered amp. I was hoping for a bit of magic in this case too.
I'm happy to report that I did experience some of the magic that has earned the Decware amps almost a cult following. The magic was revealed in the massively holographic imaging and soundstage this amp provides. It's huge! There really are no speakers in my room when I listen... I just hear music. The amp is fast paced, precise (not your stereo-typical tube amp!). Cymbal splashes are especially immersive. They smash and decay for what seems forever. Vocal and acoustic music is where this amp shines, but I did spend a fair amount of time listening to metal and industrial type music and it never got congested or busy as some people have reported. Another plus for the amp is that, in my system anyway, it is dead quite. No transformer hum, and absolutely no hum from my speakers as well. This is a common problem I've found with many tube amps.
Does the amp have a weakness? Well of course it does. Nothing at this price point (around 900 bucks) does everything right. As I mentioned, the range of speakers that will work with this amp is very limited. The other lacking area I found is that the bass is not even close to quality of bass my solid state Audiolab power amp cranks out. For bookshelf speakers the CM5 are capable of some pretty convincing bass, but the with Zen amp, this was largely missing. But if you live for the mid-range, the Zen has it in spades.
Ergonomically, you are going to either love this amp, or hate it. I sorta dig the quirky, utilitarian old school look of it. Some may not. A neat feature is the bias switch. You can flip this on the fly (if you don't mind a loud pop coming from your speakers), and as my friend Jan reported, totally changes the tonal character of the amp. One setting sounds a little more lush, a little more warm. The other setting seems to have a bit more attack and is brighter sounding.
So to sum it up, this is an "A" rated amp. I would have given it an A+ if it only was a bit more powerful. At least 6 watts and my B&W's would sing! And if only the bass was as good as the glorious mid-range and precise high end. Perhaps if I auditioned it with more suitable speakers, I would be 100% blown away. But, for the the price you pay, this is one spectacular little amp.