## delay modules that can be used for physmod/waveguides

Device/Module Wishlist

Original topic on PlanetZ: https://forums.scopeusers.com/viewtopic.php?t=12515

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Posted: Thu Apr 29, 2004 1:14 am
by kensuguro
ModIII has modulated delay, and I can use it to do some very basic physmod but the problem is that it the delay only takes in modulation in units of time. To keep the topic simple, I'll just say that the delay time needs to be controlled so that they generate pitch. (hz to ms required for 1 cycle)
I can calculate the pitch from the MIDI notenumber and convert that into millisec using a calculator, but the logarithmic/exponential operation required for that task isn't available in the mod environment. Curve scale is logarithmic to a degree, but not accurate enough to create correct pitch.
I'll post a patch up soon demonstrating a simple karplus-strong algo, so you can see what I need the delay module to do.

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Posted: Thu Apr 29, 2004 5:18 am
by kensuguro
Well, after an afternoon of experimenting, I can conclude that it's impossible to get a delay line working in Mod. I don't know how they implemented the feedback converter, but somehow, everything that gets fed to the delay line turns into a sin wav. It's wierd. I know in my head that if I fed a pulse of noise into a delay feedback chain, there is no chance that it's going to turn into a sin wave.
Then, it's the modulation delay modules who don't return the delay at original volume. (I need a "real" delay that just replays what it's fed) The delay modules take away 6-7 db per cycle, and makes creating a delay feedback chain impossible.
So folks, I guess it's time to wait for the SDK. There's gotta be a way to do this. CW obviously used the Karplus-Strong algo in six-string.. and building on the waveguide theory, I was about to make a bowed string modeler of some sort.. But I guess I was dreaming. lol. Did a fair amount of research tho.