No sound from external audio / Sub 37

[Synthesizer Patel]

If I plug something into the external audio in on my Mom I get no sound. I tried running the output from my Sub-37 into ther Mom's external audio input but nothing. I also tried a Korg Monotribe with the same result. The Mom still outputs sound but when I turn the mix knob clockwise I get nothing from the Sub 37 or other hardware. . Is the Sub 37/Monotribe not Eurorack voltage compatible?

My real issue is that I bought a sub oscillator intending to run it into the external audio on the Mom, it is a Eurorack module but I have not received it yet so I have not yet tried it. Any ideas?

PS - I just tried running the Sub 37 through an amp into the Mom as mentioned in the manual but still nothing.

[_DemonDan_]

If I plug something into the external audio in on my Mom I get no sound.

Hi Patel,

From your list of gear, I get that you are "experienced", but I have to at least ask:

Is your Filter open enough to be heard and... is your VCA's envelope being triggered, either by a key press, with the SUSTAIN switch set to ON or, by setting the VCA MODE switch to ON?

(Sorry to ask but, as Stevie Ray indicated, I'm an idiot )

If your answer is, "Of course I did all that first," then I apologize in advance, and we can move on to the next level of troubleshooting.

[Synthesizer Patel]

Thanks Dan, yeah did all that. So I called Moog and they said that the external audio input is designed for standard Eurorack voltages and that line level may not work without a transformer or amplifier. So I used the out jack of my keyboard amp and ran the Sub 37 into the external audio jack and got a lot of feedback when I rotated the mix knob clockwise so at least we confirmed that the jack is working. I'm really not too worried about it, I will be plugging a Pittsburgh Audio Waveforms as a sub oscillator into the external audio jack, the Sub 37 was just for a test. As long as the Eurorack oscillator works then I am fine. I do not plan to plug anything else into that jack so it does not matter to me. I'll let you know how it went after I receive the module.

[Synthesizer Patel]

OK a Pittsburgh Modular Waveforms multi-oscillator worked perfectly plugged into the external audio jack. So now my Mom has at least two oscs and can be more because the Waveforms can output more than one osc at a time. I need to get some stackable cables. Here is a picture of the rig. Everything plays nicely with the Mom.