Amp works well, but has narrow mains band. I am in USA and mains where I live are 122 VAC. Toroid expects 110 vac but gets 122 and outputs 22 vac. So rectifier then puts out 27 VDC. Blew 2200 uF 25VDC caps right off. Then I installed 4x 2200uF 50 VDC rated Low ESR caps instead. Put on underneath side of circuit board to make them fit. Then I installed a 62 ohm 5 watt resistor. Heat sink then runs pretty consistent at 69 or 70 degrees C. Probably needs slow fan or bigger heat sink.

Great project! Could use a little more protective packaging and the heat sink tears the bag, but package arrived in good writing order. Please advise if this input power transformer is suitable - it's hard to find and we need English instructions, though board is very clearly labeled good job :) https://www.newark.com/triad-magnetics/vpp36-1560/power-transformer/dp/37B9213

I bought this kit months ago and I am having trouble finding a transformer for it, so you guys sell one? or can you put a link to one that will work? Thanks

Very nice kits, all complete. The Chinese manual is very good to understand. Anyway it's easy.