oscillator only trouble
when trying to troubleshoot a patch which doesn't make sound,
or has lost sound on the oscillator we have to consider two knobs in particular ; tune knob and pwm knob
-make sure your tune knob is turned to around 12 o'clock, or half way through the range of the knob.
this is because the tune knob is responsible for pitch or frequency of our sound, which can be pushed either below or above audible range. little turns of knobs on modular synthesizers make a big difference. try turning slowly and listening carefully to the range you have on your oscillator, so you get a feel for where it sounds and what relative frequency is where.
-start with your pwm knob turned all the way or very close to all the way to the left, or the starting point of the knob range.
this is because pwm, which stands for pulse width modulation, lengthens and shortens the pulse width of your wave. depending on where it is, and where your oscillator tune knob is, you may be pushed out of audio range. turning the PWM knob up will increase the range of modulation, which is desirable at different times, and especially fun with a CV into that jack. pwm can add complexity to systems where you have only one oscillator, and it is especially useful for simulating string sounds.
if you had a sound from your oscillator before the filter, and it goes away after being run through the filter; resonance knob and the frequency knob
-try turning your frequency knob almost all the way, or all the way to the right. you can try slowly turning to the right and left of that point, and depending on the frequency of the signal coming from the oscillator, you will eventually find a compatible range.
when the knob is turned all the way to the right, the filter is barely cutting off or filtering any of the oscillator signal, which gives you the best chance of hearing your oscillator, regardless of its frequency. it's important to know that when your oscillator "tune" knob, or the frequency of the oscillator changes, you will be left with a new range to work with on the filter frequency knob as well.
-the resonance knob can start at all the way or almost all the way to the left, or starting point of it's knob range. you can try turning the resonance knob up with different positions on the frequency knob, to get a sense for the additional high frequencies that your resonance knob will be able to pull out, depending on your root pitch. try turning the knob slowly and fully on a few different frequencies, so you start to get a sense of the ranges you have to work with.
it is recommended, especially when you are new to patching, to simplify a patch to troubleshoot it. for example, if you have a large patch and something goes wrong where you can no longer hear your sound, try removing some of the cables. the easiest way to figure out what is going wrong in your patch is to start at zero, and slowly work your way back up so you can check each part of your signal flow. start with the oscillator going to the vca, and the vca going to the speaker left/right in. turn your tune knob and pwm knob slowly, to get a feel of the audible ranges.
once you can hear your oscillator, you can add in the filter by going from your oscillator out into your filter in, then from your filter out into your vca in and the vca out into the left/right in of the speaker. if you could hear your oscillator okay before, but not now, then you know you have to adjust the frequency knob on the filter, and the resonance. once you have your audio path is secured, you can start to add back in your lfo's and gates, one at a time, to note the affect it has on your patch. the more modules and cables you combine, the more complex your patch or signal flow is, and the more likely it becomes that something moves out of the desired range.
don't give up! it's similar to learning a guitar, clarinet, or any other instrument, where you sometimes lose your ability to sound out for a second.