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OK I've wandered off the "Class D" reservation and started building this old, simple Class A design from a Chinese kit. I was going to post this in the "Cheap EBAY Class A" thread but my ebay order vanished, so I ended up getting the same kit from Alieexpress. Enclosure is re-purposed from a crappy old busted Korean amp I found in the skip. I just got one channel built and working, I have a big chunky Altronics Aussie made heat sink but I havent drilled it yet, so I'm using the heatsink from CrapAmp for test purposes - I had to pile some old PC heatsinks on top to stabilise the temp. The mutimeter is in temperature mode so it has stabilised @ 54 degrees.. and it's a HOT day today. Link to the original reference docco, hosted on Elliot Sound Products site: http://sound.au.com/tcaas/index-1.htm Another link: http://swansonc2012.blogspot.de/2012/05/jlh-class-amplifier-1969.html This amp fairly easy to power, as it uses a single ended 24DC power supply. In fact a lot of people report very good results using a SMPS, so I got the best specced 120W SMPS I could find at reasonable price, an Altronics unit. This has made the build massively easier than it would have been. I thought I'd try a Class A amp after borrowing a (very well made DIY) 5W SET amp and trying it on the HF section of my active speakers. Was pleasantly surprised as I didn’t expect much - but it's the only bit of gear I've swapped in that my wife has made a positive comment about the sound (and I matched EQ and levels exactly with miniDSP and measurement mic)... so seeing what I can do for a low cost solid state Class A amp to try. I've left the kit "stock" except for the coupling capacitors, replaced the 1uF "Spirit" brand caps with ERO MKT8122 2.2uF caps. I'll shorten the leads to the power transisters, ultimately I'll use one of these mounted across the front of the enclosure: http://www.altronics.com.au/index.asp?area=item&id=H0545 Hoping the total build cost to come under $200 - plus a lot of fun fiddling with it. I havent adjusted the voltage or resistors to bias it, although it appears to come with parts chosen for exactly 24VDC which is what I'm feeding it.