The infamous Gaincard. The father of simplistic amps with an astronomical price to match. There are many Gainclone kits out there, but I believe this to be one of the best combinations out there - high quality dual-mono boards (Neurochrome in this case; the leader in the field), dual-25v linear regulated supplies (massively increasing bass output and reducing noise), toroidal transformer and the addition of a preamplifier. Bought alone, this stuff is over $600. It’s only ever been used for testing, and never pushed hard (up to 40w output/channel @ 150hz, to test for any voltage drop under heavy load for the regulators).
Kit includes:
*2x Neurochrome LM3886DR boards, complete and tested ($180US each)
*1x Stereo KMTech Preamplifier w/sub out, ready for op amps of your choice - untested ($80)
*2X Linear Regulated Power Supplies for amps (tested) ($60)
*1x Bipolar Power for pre-amp (tested) ($30)
*1x 300VA dual-25v Toroidal Transformer (tested)
*ALPS dual-gang volume control, not pictured ($30)
Bought all this stuff over the past few years, however now I’ve got other hobbies to attend to. Assembled this will give you a a ridiculous sounding stereo amp with up to 68w/channel. The original amplifier using these chips was over $6k, however using some linear supplies and a preamp should have it sounding even better than the original.
I won’t separate unless a pretty significant offer is thrown down for each part (and even I’ll only separate the pre from the power amp), however I’m chasing $250 for the lot. This is seriously discounted from buying everything new, plus most of the hard work is done for you.
You will need an enclosure and heat sinks, plus all the interconnects. Can supply an IEC jack if you need it.