[Stk] Wah-wah filter?

[Robert Oschler]

Hello Steve,

Thanks, that's just what I was looking for and double-thanks for the
Guitarix link.

Robert

On Sat, Oct 5, 2013 at 10:32 AM, Stephen Sinclair
<sinclair at music.mcgill.ca> wrote:
> On Sat, Oct 5, 2013 at 1:23 AM, Robert Oschler <robert.oschler at gmail.com> wrote:
>> Hello all,
>>
>> I'm a veteran C++ programmer but I am brand new to the STK.  Although
>> somewhat math challenged I do know basic DSP principles.  Is there a
>> built-in effect that creates a good Wah-Wah pedal effect?  If so,
>> where do I start poking around to use it?  If not, are there some
>> low-level filter effects I can use to build one?  Or do I have to go
>> it alone and create a separate block of code that does the DSP
>> operations necessary to create the Wah effect?:  Note, need it to be
>> fast enough for real-time processing.
>>
>> http://en.wikipedia.org/wiki/Wah-wah_pedal
>>
>> For the guitarists out there, I want to create a truly solid Wah
>> effect that really sounds like a mouth opening and closing around the
>> sound, something with some body to it, instead of an adjustable cutoff
>> filter that sounds more like someone simply twisting the Treble knob
>> on a stereo (is there some resonance processing involved with
>> achieving an enhanced Wah effect?).  I'm going to use the effect to
>> process the sound output of my current STK waveform output.
>
>
> Hi Robert,
>
> So there's a bit of work out there on wah wah pedal modeling if you
> search google scholar.  One that jumps out is Julius Smith's work
> which specifically shows how to emulate the Cry Baby pedal, perhaps
> it's of interest:
>
> https://ccrma.stanford.edu/realsimple/faust_strings/faust_strings.pdf
>
> In general (if i understand correctly) a wah wah pedal *is* just a
> resonant low pass filter.  You might be able to use STK's TwoPole
> class to implement it.
>
> Not sure if that answers your question though, since I don't know
> exactly what you mean by "something with some body to it."  (Not a
> guitarist.)
>
> By the way if you just want some good guitar effects and don't want to
> implement it yourself I suggest checking out Guitarix:
> http://guitarix.sourceforge.net/
>
>
> Steve



-- 
Thanks,
Robert Oschler
Twitter -> http://twitter.com/roschler
http://www.RobotsRule.com/
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