I recently bought a pair of premade DIY pass labs Aleph 3 monoblocks.
When I turn one on, silence. But both, and whine develops.
The only thing that seems to stop it is if I touch the earth of one of the RCA inputs to the chassis of one of the blocks.
Any ideas on what could cause this? Or how it could be corrected? It's rather persistent.
When I turn one on, silence. But both, and whine develops.
The only thing that seems to stop it is if I touch the earth of one of the RCA inputs to the chassis of one of the blocks.
Any ideas on what could cause this? Or how it could be corrected? It's rather persistent.
Psssst! Pictures would help. And it seems you mean Audio GND. Earth or PE is that thingie for safety.
Overviews of each board
Close ups of the main board, different angles to show all of the components.
It's just one of the two monoblocks, I've had a couple of people look over it and both say that this one looks the culprit (due to poor soldering) I'll send more pics if needed.
Close ups of the main board, different angles to show all of the components.
It's just one of the two monoblocks, I've had a couple of people look over it and both say that this one looks the culprit (due to poor soldering) I'll send more pics if needed.
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remove any direct connection betyween Audio Gnd and chassis , including that one from XLR header on pcb ( neg leg grounding to chassis)
check with ohmmeter that you don't have connection between case and audio GND
install CL60 or simillar NTC between main GND point on power side of main pcb ( GND at cap bank)
that should take care of zinging and whining
except that we are always eager to whine when we see Pass amp cloned out of our circle
that greedy and possessive we are
check with ohmmeter that you don't have connection between case and audio GND
install CL60 or simillar NTC between main GND point on power side of main pcb ( GND at cap bank)
that should take care of zinging and whining
except that we are always eager to whine when we see Pass amp cloned out of our circle
that greedy and possessive we are
Wow that was quick 🙂 I hadn't even finished editing the post for grammar and spacing!
Ordered CL60's
My guy wants to know:
Which connections is the NTC connecting to?
Power ground and audio ground? Or power ground and chassis?
He's not interested in the Serbian fertility ritual, but he says that it will still work without it...
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Yeah, we removed that, and currently replacing it with a CL60 NTC.
He's not 100% sure if that's right though.
Attachments
HIGHLY recommended reading:
http://hifisonix.com/how-to-wire-up-a-dual-mono-bloc-amplifier/
Edit> The same basic principles apply for seperate monoblocks (And thanks again to Bonsai for all these great guides!).
http://hifisonix.com/how-to-wire-up-a-dual-mono-bloc-amplifier/
Edit> The same basic principles apply for seperate monoblocks (And thanks again to Bonsai for all these great guides!).
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They don't look diy to me, but rather like the knockoff amps that are being sold on AliExpress et al for commercial gain. Is that the case here?
Do I really have to spell it out for you?
You bought a commercial offering that is more than likely infringing on intellectual property rights, makes unauthorized use of a trademark for false advertising purposes and completely disregards the intention under which the circuit was released to the public (for DIY use, in case you didn’t know).
Then of course the amps don’t work as advertised and you come dragging along asking for help in the very community that you’re ripping off, not even bothering to make the effort to post pics of the circuit in question. And on top of that, you act offended when you’re being called out.
You bought a commercial offering that is more than likely infringing on intellectual property rights, makes unauthorized use of a trademark for false advertising purposes and completely disregards the intention under which the circuit was released to the public (for DIY use, in case you didn’t know).
Then of course the amps don’t work as advertised and you come dragging along asking for help in the very community that you’re ripping off, not even bothering to make the effort to post pics of the circuit in question. And on top of that, you act offended when you’re being called out.