filter waveform question

[Ingo Debus]

Paul Eccles wrote:
> If I have two second order filters and whack them in series, what are the
> two new parameters I've just scored?

You have two fc and two Q parameters, giving a total of four independent
parameters.

> Also, there are second order filters that give you independent control of
> more than two parameters. The Tow Thomas biquad is a good example - cut-off,
> Q and gain.

Yes, filter gain is another parameter of course. I omitted that because
gain only contributes to the level, not to the waveform. But, if gain is
included, the number of independent parameters is filter order plus 1.

Ingo