Combining / "morphing" sounds by modulation?

[patniemeyer]

I'm looking for techniques to combine two dissimilar sounds for a sound effect. Simple approaches like combining them and playing with the envelopes and equalization are not not working well. I found some nyquist code for a ring modulation and tried using that to add in a bit of the sum and difference, thinking it might help blend it a bit, but I don't really know what I'm doing

My questions are:

1) Are there techniques for combining sounds using nyquist that I should try?
2) Are there other plugins that implement sound "morphing" or interpolation of some kind based on the direct waveforms or spectrums?
3) Is there a way in Audacity or with nyquist code to map the envelope of one sound to another?
4) Is there a way in audacity or with nyquist code to map the spectrum-envelope of one sound to a dynamic filter to be applied to another sound?

If none of these exist I am thinking about trying to write #3 and #4... not sure how easy they'd be using nyquist (which I'm not that familiar with) but I think I could do it with an audio processing library in another language.

thanks!

[steve]

There are many possible approaches (possibly limitless).
Could you narrow it down a bit? What are the sounds, and what is this for?

[Trebor]

3) Is there a way in Audacity or with nyquist code to map the envelope of one sound to another?

You're looking for an "envelope follower" ...


Steve's "dynamic mirror" plugin will also do that.

4) Is there a way in audacity or with nyquist code to map the spectrum-envelope of one sound to a dynamic filter to be applied to another sound?

Vocoder does that.

[patniemeyer]

Could you narrow it down a bit? What are the sounds, and what is this for?

At the moment I'm trying to combine a cat meow and a rasping sound to create a cat-monster roar... i.e. imagine a giant cat roaring in a godzilla like way

I'm hoping the envelope follow and vocoder mentioned above will help in combination with some regular mixing.

Thanks!

[steve]

You could try using the "Sliding Time Scale / Pitch Shift" effect to lengthen the "meow" and progressively lower its pitch, and crossfade that with your "cat-monster roar".

If you don't yet have a "cat-monster" sound, you may be able to use or adapt a sound from https://freesound.org/