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Master Voltage Offset for CV Outs

@odevices

Hi,

I’m not sure how common this relatively minor issue is but it has always been something that ever so slightly bugs me. When I set a CV out to 0v (0C.00), there is always a slight positive bias (checked using the er102 slope ins), it actually works out to be about 0.004v, so nudging the pitch out by about 9cents, if I try the next note it’s correct (0C.50 = 0.083v). Setting the CV out to 0C.04 produces the same voltage output as 0C.00, as you would imagine.

I had an idea that might be easy to implement and could work around this issue. If there was a setting on the 102 to allow you to offset the whole tracks voltage by a given amount, in my case offsetting this by 0.004v positive, would allow me to have everything line up, 0C00 and 1C00 would be exactly 1v apart.

As it is I tend to stay away from the first octave (generally the first 12 in the index), so as to avoid this detuning.

Thinking it might make sense to put in the admin page somewhere?

Cheers

Ross

I think it’s a very common problem in euro, as I understand from speaking to people more clever me, it’s down to the psu. I don’t think ther s much to do about it, besides looking the other way and avoid 0V all together (as you already do)…

I think yr right but my feature request could work around it nicely.

Are you sure all your oscillators respond the same to the out of tune 0V?

Yeah, I’ve got em all pretty well calibrated. None of em are perfect of course, that’s what makes it sound good!

Ok the reason I ask is because although they are perfectly calibrated and track well with other voltages than 0V, they still might behave differently on 0V, in which case you won’t be able to fix “the issue” on the sequencer.

A friend of mine had a similar issue, but only between his rene and his shapeshifter… All other voltage sources and oscillators worked fine.

Ahh I know the shapeshifter rene issue, the v/oct input on the shapeshifter has a an offset for when no voltage is connected. I think the rene outputs a low ??capacitance?? (probably using the wrong terminology here, can’t remember secondary school physics!) voltage, which means the shapeshifter tracking is very odd when driven from direct from the rene (it gets mixed with the fixed offset), if you send the rene via a buffered mult all is well. If only eurorack was more standardised!

Had both the shapeshifter and the rene at one point and it took me quite a while to work out why sometimes it was wonky and others fine (not noticing the use or lack of the buffered mult in the various patches).

Have you tried shifting the note display offset to 0b.00 (from the track configuration screen)?

In 12ET, this will cause index=1 (0.083V) to correspond to 1C.00 and so on, thus shifting the voltages up by 1 semitone with respect to the index (or 11 semitones down with respect to the displayed note value).

Not really no, I’ll give it a go. I’m sure it’s easier to think in multiples of 12, than multiples of 12 + 1 but I can see what you’re getting at. :slight_smile: