[sdiy] VCO Linear Voltage

[Scott Gravenhorst]

"Jerry Gray-Eskue" <jerryge at cableone.net> wrote:
>
>Question:
>
>How is the linear voltage control of frequency useful on a 1 volt per octave
>VCO?
>
>Thinking about it, this control input is not making musical sense as it
>varies the output frequency at a direct relation to the voltage in. In other
>words at low frequencies the variation in Cents will be much greater than
>the variation at higher frequencies. The rapid fall off of relative
>variation would seem to make it an undesirable type of control.
>
>What am I missing here? Is this useful for modeling the timber of some
>certain instruments or perhaps other acoustical artifact?

IMO, it is/was used in synths (very few) where the price point was a problem.  Expo tends
to be a tad more expensive.  The PAiA FatMan uses linear pitch control.  The scaling is
handled by the MIDI to CV converter.  It is a more difficult to do simple modulation of
the pitch with linear CV, one needs to scale the modulation based on the current CV. 
With the FatMan, there is an unintended CV modulation entry point on the VCO because it
uses a 555 timer.  Simple slow modulation can be applied to it without the problem Jerry
mentions.


-- ScottG
________________________________________________________________________
-- Scott Gravenhorst
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