Best DIY SE amplifier?

[cumbb]

The Zen you do have built? Very gooood amp;-)
I would try a lot.
First: I would remove the input resistors, R5 and R9. I will get, maybe, a lot of other, audible distortions. I would try, to get a handle on these by proof parts: resistors, wires, caps...-)

 

[bwaslo]

bwaslo your board need a professional touch up to be honest.the routing is done in a silly way kind of takes away the credibility of your claims. Have you considered revamping it? And may be you can ship a unit out to everyone to listen to. It is hard to sell a new amp when all those established designs and designers are out there!
No offense. A feed back for a great DIYer as you are.

Thanks for commenting, Kinku.

But as for the routing, it is specifically done that way so that the board could be etched at home as a single layer (as some DIYers still like to do that). Other than that, the considerations were the placements of the output transistors (they need to be a distance from each other for heat management) and accessibility of the bias control. And so the amplifier can be easily expanded with more outputs with additional boards and needed heat sink distribution. And so that ground currents flow in a good manner to avoid input ground current leakage. It's far from just random. The layout is WAY MORE than adequate, and I'd say near optimal, for the couple hundred kHz bandwidth of the amp (I'm a retired RF/microwave engineer -- that's where routing needs ground plane to follow traces). To tell, the truth, even if using double-sided only, I don't think I'd change a thing (of the a rev 2 layout in the article, tweaked a little from the boards you got from me, but mostly just fixing some spacing and hole sizing issues).

 

[cumbb]

... SE ...-)

Today:

Built in 2 input-caps. superb, but a little little bit rough and grainy. Curtailed the connections - (much;-) better;-) Now "conclusive"-)

I do love good amps;-)

 

[cumbb]

30 minutes ago, I changed the IRF9630 with TIP42C. This time also the sound is finer, fluider, higher resolution, less rumble. Despite 100 µF elko instead 1 µF polystyrene for the input;-)