[RE: LFO voltage?]

[Jeremy Brookes]

> Watch out.... "string" players get vibrato by wiggling their fingers both
> perpendicular to the string (positive only) and parallel to the string.
> Parallel will give (on a non-fretted instrument, violin etc) true plus and
> minus pitch variation. And in practice, even on a guitar wiggling
> your finger
> this direction will "tighten" and "loosen" the string, causing the same
> effect....
>
> I'd say that for Triangle and Sine modulations, bipolar signals
> are correct
> (+-volts) and that Sawtooth and Square waves should be unipolar positive.
> There are few exceptions to this rule of thumb.

True, I was thinking of the fretted version (being a guitar player) where as
you say movement perpendicular would give positive only. I completely missed
the idea of non-fretted instruments. Apologies.

It's somthing I've noticed when synth manufacturers include emulations of
guitar that the LFO modulation is almost always bipolar and as Harry rightly
points out this approach is fine for some acoustic instruments, for guitar
(and fretted instruments) it's not very realistic.

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