[sdiy] Roughness vs Frequency?

[Magnus Danielson]

Hi,

On 2023-01-29 07:37, cheater cheater via Synth-diy wrote:
> Is it possible to define roughness so that a sound can be said to have
> a specific amount of roughness at a specific frequency? It appears to
> me that some sounds seem to sound "rough" at high frequency parts of
> their spectrum and other sounds at low frequency parts, or others yet
> at mid freq parts.
>
> Maybe a spectral envelope of roughness vs frequency could be produced
> (kind of like level vs frequency which is just the normal audio
> spectrum of a sound)

Turns out that there exists standards and measures for this.

One place to check out is:

https://community.sw.siemens.com/s/article/sound-modulation-metrics-fluctuation-strength-and-roughness

This brings us into modulation and strength of modulation within a 
particular frequency range.

You can AM and PM detect signal and analyze their spectrum. AM is the 
simplest. Some suitable filtering and a level detector and you can 
adjust levels to match up with a particular scale for roughness. Seems 
doable.

PM/FM detection can naturally also be done and similar processing.

Cheers,
Magnus