Model No:  ZKIT1 - Zen Triode Amplifier Kit



In my quest for better sound, a name that continuously enters the conversation is Decware.  After looking at Steve's web page several times over the last year or better, I decided to take a serious look at S.E.T. amplification. The major set back was $$$.... Yes again its the green, not so much that the amps are expensive but the dollars per watt. Recently I checked back with Decware and found to my liking a DIY SE84 amp kit for a measly $300, but I still have some concerns.

Is 2.3 watts per channel enough?

At this price how much quality can I expect?

Will I really hear the EL-84 tube magic?

Is this kit easy enough for a beginner?

Well it time to find out, I ordered the kit and I am ready to build.

Here is a link to the Decware DIY Kits..



Today, I spent most of the morning listening to the Decware, and have to admit I am surprised and ultimately pleased with the overall performance and sound. The only thing I could ask for is a touch more headroom, which I intend to solve by running a pair of these Bi-amped into my Cornscala's. I really feel I need to clarify this statement so it can not be misinterpreted. With 100+db speakers, and a 12x18 room, the average spl at full output is approximately 94db, which is plenty loud, but occasionally I like to irritate my wife, and that is going to require an additional 3 to 6db. Her breaking threshold is 100db

Around 11am Johnny 5 showed up with an Ebay purchased EL-84 powered s.e.t. amp that he wanted to compare to the Decware. Johnny 5 told me did not like the Ebay amp at all, and because this was his first experience with EL-84 set amplification, he was discouraged about the low powered s.e.t.'s altogether. I played a few passages strong in bass to get him a feel for the Decware, because his major complaint on the DIY Ebay rig was "bass is lacking". After only a few minutes he exclaimed "The Decware trashes the Ebay junk I bought!" Next I installed Johnny's amp, which by the way must weigh a pound and a half, and proceeded to listen; instantly I could tell his assessment of the amplifier is correct, which led to some testing. I had no intentions of breaking out the oscilloscope, but I had to know what was going on with Johnny's amp.

Testing Johnny's DIY Ebay amp... First I hooked up Johnny5's new amp and feed it a 200hz sinewave. Initially the output followed the input nicely, then I dropped the signal to 30hz and the amp trace dropped off the screen, confused I reset the scope got both traces back. What did I do wrong? I thought to myself. Next I increase the frequency to  2khz and watched the amplitude from the amp increase tremendously leading me to believe the amp is non-linear. To verify its not my gear or something I am doing wrong, I hooked up the Decware.

Decware ZKIT1-DIY test: Already I am thrilled with the Decwares performance, but to verify what I am hearing an in comparison to the Ebay rig it was necessary to perform the Identical tests as above. I started with 200hz, once again the traces followed nicely. Next I dropped to 30hz and noticed only a very slight reduction in output, which I expected, what I didnít expect was a near flat sweep from 50hz to 20Khz. I had to go back and verify what I was seeing multiple times, what I found is that the Decware is an amazing low $$$ amplifier that easily competes with or betters my much higher dollar amps in all areas except power output.

My overall opinion of the Decware DIY is this is an incredible amplifier, that deserves all the praise I have given it and more. I am impressed with its quiet operation, and will recommend this amp to DIY'ers with high efficiency speakers, that listen to music rather than look at it.

Build quality: Steve did a great job obtaining incredible parts, that won't "break the bank", and work nicely together. The transformers are of adequate size and are quite heavy, nice to know there is some iron in there. The circuit board uses heavy traces, solder masking and, every part is labeled to keep the build as simplistic as possible. There are only a few parts that I would like to swap out, but that is personal preference, and may not improve performance.

Imaging is impressive, I found myself enjoying instrument placement, and even turned my head to look for a sound, but as soon as I turned it was gone, as I turned my head back the sound returned, it was subtle and pleasant, and I am not sure I had ever noticed it in the past.

Speed and accuracy: When I see this as a defining quality often I roll my eyes. When I refer to speed in an amp, I am referring to bass, and I feel that the bass is accurate, not as bloated as some push-pull amps but quick and full, even pushing a 15 inch woofer the bass sounds very natural. 

Well that's it... I like it....what more can I say.

Dave Harris.....What I don't know is alot. - amateur advice giver.
Gothover @


My scope readings:

Both channels - Decware

Red is input 0.5v scale yellow is output 5v scale. 1500hz

Beware of Ebay's audio jewelry.



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by Steve Deckert