[sdiy] Craig Anderton's Multiple Identity Filter

[Tom Wiltshire]

On 2 Nov 2016, at 22:05, Olivier Gillet <ol.gillet at gmail.com> wrote:

>> How do you cross-fade between two filters in series and the same
>> in parallel ? If series is a(b(x)) and parallel is a(x) + b(x),
> 
> Not true crossfading but something like this:
> 
> a(k b(x) + (1-k) x) + (1-k) b(x)
> 
> k = 0: a(x) + b(x)
> k = 1: a(b(x))
> 
> Or two independent crossfaders - one as a final stage that crossfades
> between a(x) and b(x) ; and one at the input of a that crossfades
> between a and x.

Nice trick. What do the midpoints sound like?

If you've got a(b(x)), you've got b as the first filter, and a as the second, so filter b is getting the whole input, and filter a is getting a mixture of the input and filter b's output. Then the output is a mixture of the output from the two filters.

I can't imagine what that does to the sound.

Thanks,
Tom