[solved - using the correct AC power adapter helps alot :P ] Light's are up but no sound


just finished two smr4 voicecards and the ambika board itself. Everything lights up. All knobs and encoders do what they are supposed to do. Menus, Sequencer, Midi, whatever you like works … except for the sound.

On both voicecards the red light is on and the green lights blink, whenever I send midi. I tried all Audio jacks, nothing. I even changes the TL072s … nothing.

I think I would need some troubleshooting tips on what to measure where?

I currently don’t have a SD Card. But I don’t think that should matter for the basics? And, and maybe that’s the problem here(?),
when doing the ‘Power supply testing’ I can measure everything correctly except the -8V on the blue pin on JP1
Or maybe I’m doing it wrong?


No wonder nothing is working if you don’t have a -8V source

I bet you’re simply not using the right kind of power supply. Which power supply do you use?

Yeah, what Olivier said. You need a 9v AC adapter, not an AC to DC adapter.

Oh boy you are right! I guess you shouldn’t debug something at 4am ^^ and use the shruthi supply
And now even the “reverse” 4004 diode makes sense :stuck_out_tongue:

Sorry for the interruption


It’s amazing that when you actually do it right … it starts working like a charm :smiley:

Bought a 12V AC supply, changed the voltage regulators … and now it’s working yay