I’ve got a patching puzzle that I was hoping someone could help me out with. First, here’s what I want to do…
I want send a random voltage (within a certain range) to the Cutoff in of a MF-101 whenever I hit a footswitch. The idea being that as I play my Voyager I can step in a random cutoff value that is held until the next time I hit the switch.
So here’s what I tried: Footswitch into S/H in (I tried them both) on the CP-251 then S/H out to Attenuator to MF-101 Cutoff (with the Voyager running through that pedal). However, every time I hit the switch it seemed not to do anything at all, or sometimes it sounded like it was sweeping the cutoff just a touch(?).
I’m wondering if I’ve got the right idea, for starters, or if there might something particular to do with the type of footswitch I’ve got? I don’t know anything about it except that it works for tapping tempo on the MURF.
Try making a direct connection from the cp251 S&H to the 101 first to see the effect of the S&H to the cutoff. If theres no difference then you know that its not the footswitch.
If there is no difference then you may want to try opening the filter up a bit more or increasing the resonance a bit.
Ive noticed on my MicroMoog that if my filter cutoff is around the 12:00 position the sample and hold voltages will be more often below the cutoff point so it only rarely effects the filter. If this helps you at all then great. If not then I don’t know because I don’t own the Voyager or the Footswitch.
You might also try triggering the S&H with something else other than the footswitch, for instance, the envelope follower outpuf of the 101. That shoudl be a signal of sufficient strength to activate the trigger.
Ive never really tried using a gate signal to activate S&H so I can’t reccomend anything further.
also, make sure you are putting the switch into the trigger in, and not the “in” jack. if you connect it to the “in”, you are essentially sampling the foot switch, or position of the pedal.
also, make sure all powered jacks are either unplugged, or have TRS cables in them. one mono cable will short out a pedal working.
You need to plug the Footswitch into the TRIG input - not the S+H IN Input (In fact the S+H IN Jack is normalled to the noise source). If you do this (and plug nothing into the S+H IN jack) you will get exactly what you described - a new random voltage held until the next footswitch press. Try removing the Attenuator from the path and you’ll hear the effect much better…
Also with the Moog FS-1 - the trigger will happen on the release of the footswitch, not the press. The FS-1 is normally closed, press to break - which works for the Voyager and MuRF gate inputs…and it works in this application too, but as I said - on the switch release…
Think of the S+H IN jack as an input for CVs, and the TRIG IN as the gate input that instantaneously passes the CV @ the S+H IN to the S+H OUT when the gate goes from low to high.
You can also try a slow triangle wave patched to the S+H IN with what you’re talking about, (w/ the footswitch connected to TRIG IN) - you can tap rhythms on the footswitch and get a cool rising/falling staircase modulation…
Worked like a charm! Thanks very much Steve et al. I guess I’d attenuated it too much before…
This leads me to another question: with the cutoff being driven by the gated S/H (without any attenuation), I noticed that it was stepping to ranges within maybe 10 degrees of the original knob position on the fooger. This is more practical for musical uses most of the time, but how would one sweep the entire range of the filter? Or is it just a feature of how the pedal accepts CV signals in relation to the knobs? I suspect the latter.