[sdiy] Oscillator precision

[patchell]

    I was wondering where you came up with 600ppM....well, if my arithmatic is
correct, that is 1 cent, which is probably about as good as you are going to be
able to get.  My piano (a real piano)  slips about 10 cents in a month, which I
can't notice (the piano tuner does)...

    However, there are a lot of factors to consider for oscilators, and I
assume you are speaking of VCOs, other than absolute tuning acuracy...in fact,
we just had a big discussion about this just a month ago.  Several of us, for
instance, are working on ways to make the scale factor of the VCO independent
of temperature.  Others are working on ways of making the VCO core independent
of temperature...temperature drift being the big killer...

    But from personal experience in tuning VCO's, getting them tuned to within
1 cent is a pretty big challenge.  The best I have been able to do is about +/-
2 cents over 8 octaves.

Zoltan Gaspar wrote:

> Hi list,
>
> What do you think the required precision for a control oscillator should be
> for a high quality synth? If I have the note 'A' within 600 ppm, is that
> OK??
>
> thanks,
>
> zoltan

--
 -Jim
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