Tuning the scale.

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tsheets
 
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Joined: Mon Oct 24, 2005 4:21 pm

Tuning the scale.

Post by tsheets »

Man, I always have problems tuning the scale on VCOs.

I can't seem to tweak the scale trim so the frequency is exactly double across an octave.

I have a MIDI keyboard plugged in while I am trying to do this. Where should I start.. I can set both pots to near center, tune middle C, then try to adjust the scale to match the pitch an octave higher.. but I just can't get it.

Anyone else have this problem? Any further tips?

-troy

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controlvoltage
 
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Joined: Tue Aug 09, 2005 12:17 am

Post by controlvoltage »

Well I was using a strobe tuner...which might or might not be easier than doing it by ear... but when I couldn't get it dialed in in the normal method, I did it backwards.... using the scaling trimmer to get my low note and the osc pitch trimmer to dial in the octave. Or maybe I was doing it backward the first time.

Anyway, I guess my point is to try it both ways in case one is easier than the other. Also make sure that it has been on for a few minutes and is in a temperature-stable (not drafty or under a heat vent) environment, it will make it a little easier I suspect.

moogah
 
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Post by moogah »

Patience and a steady hand are your main tools here. Remember that this is a bassline synth and should probably be centered around C1 (lower C on the keyboard). Tune this up first then adjust the width setting and then repeat the process if needed. It took me a couple tries to get it right. IMHO the width of the octave is more important than the tune of the osc.

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etaoin
 
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Post by etaoin »

IMHO the width of the octave is more important than the tune of the osc.
I'd second that.

Also, don't forget that changing the width will detune the osc, so it's more than likely you need to go back and forth between the two a number of times.

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Post by Guest »

Okay... one question. Once the width (scaling) is adjusted correctly, if I mess with the tuning trim pot... it won't mess up the width, right?

I have the indent tuning knob, so I have to deal in the tuning trim to set it right at
the indent point.

-troy

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