FW: digital contents

[Paolo Predonzani]

> Yes indeed!  How much this dynamic tuning effect contributes to the
> sound of the filter is unknown.  (Also whether the effect is
> aesthetically pleasing or not.)

It is very important. My simulation is probably inaccurate but it
definitely sounds different from linear digital filters. The detuning
can be heard setting the Q to infinity (self-oscillation) and feeding
the filter with white noise at different levels (poles move).
Moreover the self-oscillation frequency (null input)is slightly lower
then the theorical value that can be calculated with small signal
frequency response.
> 
>    (2) How *far* would these poles move? Usually, the signal amplitude
>    thru the ladder is small in comparison with the bias current. (?)
> 
> Maybe not that small.  Overdriving the Moog filter is standard
> operating procedure.  (That's a good way to get a more sinusoid wave
> from a triangle.)

For 0.1V p-p input the filter is almost linear. For 1V p-p it's definetly
overdriven. Low Qs overdrive the filter more than high Qs. 
> 
>   -- Don
> 


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| Paolo Predonzani  |  email: predo at dist.dist.unige.it |
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