Chinese copy NVA PCB's

[Dr Bunsen Honeydew]

Cagey was going on a while back about them on AoS, so as they were a copy of an old incarnation of NVA I thought they could be useful for me in repairing old amps as I have to replace both boards for the new ones. If these work I only have to replace one. So I ordered a pair from China on eBay. Built them into an AP50 and switched on they sound as dull as ditchwater and within 5 minutes the two big lumps of alluminium I used to heatsink them were up to over 100deg C, definitely dangerous and illegal. I am just stripping them out of the amp to throw away then thought I would tell you lot and give a pic, so these are them half disassembled from the amp.

[_D_S_J_R_]

Hold on a minute - I've only got one pair of hands you know and can't repair boards while I'm making up summat else...

[Dr Bunsen Honeydew]

These aren't for repair they are for the dustbin

[_D_S_J_R_]

You need a stock of serviced and part-checked boards to repair older out-of-warranty amps I thought, hence my comment.

[Dr Bunsen Honeydew]

The old board can't be put with the new one in stereo amps.

[_D_S_J_R_]

Why I've been treating them as pairs as best I can do

[Dr Bunsen Honeydew]

I could try and find why the copy board is not working properly but I can't be arsed. The amount of heat being generated probably means the quiescent current is way out, but that doesn't explain why the music is so duff and muddy, not faulty type muddy but just not NVA clarity so I am not going to waste time on it.

People should take this as a heads up about these Chinese boards sold at eBay and not just NVA, but it shows they haven't a clue or just don't care. So anyone thinking of buying any of what ever design or ilk, my advice is don't. You will just waste your money like I have just done.

[Yomanze]

Goes to show that layout is just as important as components, other issues aside.