Foobar 2000 MathAudio type room correction using minimServer

[MusicMole]

I have previously reported having had some success with using parametric equalisation with minimServer for room correction https://forum.minimserver.com/showthread.php?tid=5548 - with some limitations.

I have since tried Foobar 2000 with the MathAudio plugin and find the corrections that it makes ‘better’ overall for a broader range of music (to my ears at least) i.e. tracks which are bassy are controlled but tracks that don’t need controlling are left alone. I think this is because MathAudio probably limits/caps the problem frequencies rather than pulling them down.

Does anyone have any idea how to implement a MathAudio type filter please using ffmpeg filters? I have tried the soft limiter and a compression example from the ffmpeg site (https://ffmpeg.org/ffmpeg-filters.html#Examples-9), but both lead to a lot of unpleasant distortion:

Soft limiter: convOut=-af compand=attacks=0:points=-80/-80|-12.4/-12.4|-6/-8|0/-6.8|20/-2.8

2:1 compression starting at -12dB: convOut=-af compand=points=-80/-80|-12/-12|0/-6.8|20/1.9

I have to admit that I’ve had quite a bit of difficulty trying to understand these filters and what they do, so any clarification would be appreciated.

Thanks