Mounted the other bank completely. Current draw in idle about 2.3 amps. Now it seems OK. I will put everything back in the heat sink and test for longer.
I didn't read the whole thread, but i measure with my Fluke scope with 10kHz lowpass filter in, when testing the class d mono's. Do you read a good sinewave then? I don't think there is a problem with the amp...?
No, there is no good signal, see the pics in the thread. I solved one problem, but now from one bank the high side fets get warm, and the upper sine wave is distorted again.
So, still something wrong. Upper half same. After a few seconds, starts draw current. I have signal on high and low, but high on both sides looks different to low side.
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side with and without signal..can this be caused from the tl072? Audio signal is more distorted then before. If I give higher gain, above 10amps input, then it starts drawing more than 20amps,and don't go down, even when I remove input.
#72:
Does this happen with only one side of the amp or does it do it no matter which side (alone) has FETs?
Are you sure that the output FETs that you're using are compatible?
Were all parts purchased from reputable distributors?
Does this happen with only one side of the amp or does it do it no matter which side (alone) has FETs?
Are you sure that the output FETs that you're using are compatible?
Were all parts purchased from reputable distributors?
All parts are from Mouser. I dont know, if this are the orinigal fets. I contacted Ground Zero again, to give a diagram, or at least tell me the right fets.
I didnt tryed with one bank of.
But now im running out of ideas. I think its strange, that at very low power, everything is fine. If i increase output, so that the amp draws about 4-10 Amps, its starts disorting. After 10 Amps, but only sometimes, its starts draw eecesive current, so that my PS is limiting. Seems, that the high side is full open at this time, but still produce Audio...
Maybe the TVS are broken, or the signal diode on the drive board, iam not sure.
I think, it could also be the TL072, but then, i think, low and high side should be more disorted.
I didnt tryed with one bank of.
But now im running out of ideas. I think its strange, that at very low power, everything is fine. If i increase output, so that the amp draws about 4-10 Amps, its starts disorting. After 10 Amps, but only sometimes, its starts draw eecesive current, so that my PS is limiting. Seems, that the high side is full open at this time, but still produce Audio...
Maybe the TVS are broken, or the signal diode on the drive board, iam not sure.
I think, it could also be the TL072, but then, i think, low and high side should be more disorted.
So, removed the buffer stage, side by side. One side has more distortion on the upper sine wave, the other side much less. Still waiting for reply from ground zero...
