Turntable Warping (v3)

This is a rewrite/bug fix of David Sky’s Turntable Warping (mono/stereo) V2 plug-in http://wiki.audacityteam.org/wiki/Nyquist_Effect_Plug-ins#Turntable_Warping_MS

If this version is free of typos and any serious bugs I’d like to replace David’s original version as soon as possible.
The most obvious difference is that the amplitude sliders work. I think that I’ve also got the time stretching right, and it now supports sample rates other than 44100 Hz.

Testing and feedback is much appreciated as always.
turntablewarp-v3.ny (2.29 KB)

With settings: 0 / 100 / 0 -36 / 0 it does a nice job of a turntable slowing down.

With settings: -36 / 0 / 100 / 0 / 100 it is not a very good simulation of a turntable speeding up - it’s the reverse of slowing down but the turntable should quickly come up to speed.

The requirement to set the “Change Time” (what does that mean?) to 100 in the case of speeding up is weird to me but I think I understand. It is the “time” (in percent through the selection) that the “change” takes place, and since for speeding up the maximum change is at the start then it has the reverse meaning to when slowing down?

I’ll play with it some more and see if I can get a better “turntable starting” effect.

– Bill

David’s documentation does not help much with this:

"Change time: [0 - 100 percent, default 50] - the point in time in the selection (set internally to the original pitch and volume) at which the warping values change to reach and move away from this point. What this means is that depending on your start and end step and amplitude values, you can design warps that slow down then speed up; speed up then slow down; speed up to a particular pitch then remain there; slowly speed up then quickly speed up. "

Clear now? :smiley: Hmm… :confused:

What it does is to set the “original speed” point, so that if set at 20%, then for the first 20% of the duration of the unprocessed audio, the speed will vary from “Initial Step” to “normal speed” and in the next 80% will change from “normal speed” to “end step”.

Please feel free to suggest clear wording.

My main concern with this at the moment is that the version on the wiki is quite badly broken so the first thing is to fix it. I can look at enhancements later, but that’s not such a high priority.

After further testing, the version posted in this topic is less broken than the version in Audacity but it’s still not quite right and requires further attention.
Thanks again to Bill for testing and providing vital clues to the remaining problems.

thanks for making this. the version on the wiki is broken lol. =]