Differences between the old Spectrum CHOP and new Audio Spectrum CHOP

General TouchDesigner Discussion
1

Hi,

I am looking at this project by Markus Heckman soundviz/soundviz03.tox at master · wuestenarchitekten/soundviz · GitHub It uses Spectrum CHOP that converts audio to frequency spectrum and outputs 2 frequency magnitude channels.

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Spectrum chop is not available in version 2020.20020. If I try to use Audio Spectrum CHOP with the mode Time to Magnitude and Phase instead, my frame rate drops to 1fps. I assume because in the old Spectrum there was a parameter Analyze Segment which Markus set to 1 frame. And this setting is not available in Audio Spectrum CHOP anymore. What would be the way to work around that in the new TD versions?

2

Hi @dancing_pixels,

I’ve just updated the repository and all of the components are now 2020.20k ready.
The particular issue with the Spectrum vs the Audio Spectrum was that the value range has changed quite a bit. I have now changed it though to use the visualization mode.

Best
Markus

3

Thanks! I see. The way is to use Visualization mode and set the output length manually to 735 samples which would be the number of samples for 1/60s of a second, that is one frame, for an audio which was sampled at 44100 samples per second. Also thanks for sharing the projects :slight_smile:

4

Yeah - you could use the “Time to Magnitude and Phase” option as well but would have to divide the resulting values by 100 or so. The Visualization mode makes is also easier to use the higher frequencies…

Cheers
Markus