[sdiy] Boogey jitter

[JH.]

> > Personally I'm convinced that
> > a) Different VCOs have different amount and type of built-in modulation.
[...]
> Seriously, we all know that VCO exhibit amounts of phasing
> due to leakage

There is phasing (or: "beating") even without any imperfections, just from
detuning two
oscillators. Leakage can help to emphasize this in the low frequency range.
Modulation can help making the beating patterns more interesting, especially
with only 2 VCOs. All well known, nothing new.

> and that they behave (frequency whise) as the supplies behave.

There are two things that shouldn't be mixed up:
Modulation, or sync'ing, or both, thru the power supplies.
Long known in principle, too, but not really quantified yet.
And the other thing, talking about the *DC* value and "SNR" -
I won't repeat what I think of that.


> > b) If analysed properly, this could be emulated perfectly with a
"perfect"
> >     VCO, and external modulation sources.
>
> Theres no need for a perfect VCO,

No doubt. Note the quotation marks.


> > c) For my needs, expressive means of manually controlled modulation
> >     are more important than the build-in modulations.
>
> Such as linear detune for instance.
> As Harry toughtfully said earlier: if a VCO is faulty i try to fix it!

That's why I prefer to make the "linear detune" effect variable.
Dial it in, as much as you need it, instead of living with a fixed
amount.


> > I tried to explain the importance [to me] of (c) with my aftertouch
example.
> > I'm _slightly_ interested in research on (a), leading to (b), but my
life
> > doesn't depend on it. It would be fairly interesting, yes.
>
> I prefer beeing in the garden and pooking around rather having
> a swelling itching brain even looking for something defined as
> warmth/magic/fattness of one VCO singing its sorry tune of jitterbug!

So much truth in this.
Nevertheless, research, done seriously, needs dedication.
Thank God we're just doing synthesizers, and not digging up corpses
like some bold men did in olden times to get medical knowledge
for mankind!  8-)

JH.