[sdiy] 2164 Korgasmatron VCF

[David G. Dixon]

> > Sometimes doing a partial fraction decomposition of a transfer function
> > helps.
> 
> Interesting, I wouldn't have thought of that - thanks
> 
> > Looking at a transfer function as the product of some simple to
> > understand signal processing blocks (like integrator, differentiators,
> and
> > gain stages) for doing a sketch of the composed amplitude and phase
> response
> > gives you a more "intuitive" understanding.
> 
> That's pretty cool. However I have a problem figuring out what the
> Laplace plane works like. I still don't feel it naturally. Maybe I
> should go and look at the transfer functions for some basic blocks,
> that could help make it easier. I wonder what the best things would be
> to start with.

If you understand complex algebra, then replace the S's with jw's, separate
the real and imaginary parts top and bottom, find the magnitudes top and
bottom (i.e., find the square root of the sum of the squares of the real and
imaginary parts in both numerator and denominator) and plot this against w.
That will give you the amplitude, which is what you really need to know.