Looper / sampler isd1820 (Lo-fi)

I’ve made vactrol for Gate and CV, not with this schem but
maybe you have just inverted the pot’s pin of the CV pitch pot

I see. Well, I tried all possible connections on the pot. But doesn’t seem to do the trick. Really puzzled by this :thinking:

No, reversing the connections would just make the starting pitch go the opposite way as you change the pot, but wouldn’t change the direction of the CV response.

The chip responds to voltage the way it does, evidently higher pitch for lower voltage. To change that you’d presumably need to convert the control voltage: You could use an op amp to invert the voltage and add an offset to make 0 to 5 volts become 5 to 0 volts. Along the lines of:

image

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How helpful! I thought I was loosing my mind. So in this schematic do I still need the 100k pot after to track 1v/oct? Or can I rely on the source being spot on? Either way I will try set this up later today.

I would guess it’s not going to be at all 1 V/oct, probably not even exponential, though I could be wrong. You could try to wire up an exponential converter and calibrate it to 1 V/oct, but that would be a big effort and my feeling is the results wouldn’t be worth it.

I see, I’ll try this configuration and use a quantized voltage to see how musical it sounds, it is all about ratio’s anyways. Thanks! Will report back.