JLM AUDIO

Great, that was the solution. I connected -DC of VU2 with PGND of the output stages and now everything is wonderful. Thanks again for your help... Cool great to hear that fixed it. When you have 2 power supplies like this you have to reference them to each other. Yes, you're right, I would never ha...

Great, that was the solution.

I connected -DC of VU2 with PGND of the output stages and now everything is wonderful.

Thanks again for your help...

Okay, we got along right.
Because that was now my train of thought.

First of all, thank you very much for the great help


greetings

The -DC of the VU2 needs a connection to the 0v centre ground of the amp supply to make both referenced to the same 0v. This can be done by a wire directly between -DC and amp 0v I'm going to put -DC from VU2 to PGND from amplifier. PGND from the left and right output stages are connected to each o...

Since that supply is floating you will need to link the 0v from 12v supply to the 0v of the amp supply. You can do this just by linking the -in to the 0v on the VU2 inputs. With the VU 2 inputs you mean the +/- connection for the power supply, correct? As I presume the -in is the shield of the unba...

Yes, that's right, I am currently running the VU buffer with a 12 V regulator in the top right corner of the picture.
The regulator is fed by the print transformer.
The output from the reg goes exclusively to the + and - connection of the VU BUffer.

Hi, I have installed the VU buffer in my diy power amplifier, and I get a mains hum as soon as I plug in the plugs of the unbalanced inputs. When I disconnect the inputs from the VU buffer again, the output stage is absolutely quiet. I wonder if it is due to the hidden pin4 because I didn't solder a...