Name for effect that tames loud highs?

[Michael Willis]

I'm trying to develop an effect algorithm and I don't know what to call it. I want it to reduce high frequency noises that have an amplitude above a given threshold, but if high frequencies have an amplitude below that threshold, they should pass through the filter untouched (well, maybe untouched... a phase shift would be acceptable). Is there a good name for this effect? It's not EQ or LPF, both of which cause a gain effect to everything in the frequency band regardless of the input amplitude.

I want my effect to tame harsh high frequency noise without dulling high harmonics. The closest thing I've found in open source effects is Airwindows Accel/Accel2. Those names are short for "acceleration limiter", but I don't think that really describes the effect. I looked at the mathematics in those plugins, and they're not what differential calculus would define as a limit on the acceleration.

Any suggestions?

[merlyn]

Is it a dynamic EQ?

[SpotlightKid]

A de-esser?

[nevis]

"sibalancer"

[LAM]

Slew2?

[sysrqer]

Multiband compression?

[novalix]

Tape Machine?
scnr

[MyLoFy]

Reminds me of Soothe2, which is a "dynamic resonance suppressor". Definitely something I would like to have in my FOSS toolbox

[LAM]

Reminds me of Soothe2, which is a "dynamic resonance suppressor". Definitely something I would like to have in my FOSS toolbox

It seems also @robbert-vdh's Spectral Compressor can do something similar, as shown by Au5:
https://www.youtube.com/watch?v=jo_ayanaKo4&t=223s

[sysrqer]

Reminds me of Soothe2, which is a "dynamic resonance suppressor". Definitely something I would like to have in my FOSS toolbox

It seems also @robbert-vdh's Spectral Compressor can do something similar, as shown by Au5:
https://www.youtube.com/watch?v=jo_ayanaKo4&t=223s

Wow I had no idea we had anything like this, amazing.

[sunrat]

Auburn Sounds Lens can do this too. Multiband compressor with up to 64 bands. Linux native version and free for the basic one. It's one of my favourite plugins now.
https://www.auburnsounds.com/products/Lens.html

I just tried the Spectral Compressor mentioned above; seems to be also some kind of magic. It's now part of nih-plugs - https://github.com/robbert-vdh/nih-plug ... compressor
Needs some documentation as I couldn't work out if it could target multiple narrow frequency bands although it was simple to target a single band. Easy with Lens - just draw the desired buitlt-in sidechain curves.
Edit - seems one can achieve similar in SC with a sidechained external EQ.

[Death]

It sounds like you're essentially describing a Dynamic EQ/Multi-band Compressor but perhaps ones that are more intelligent such as Soothe 2 & Gullfoss.

I'm not sure exactly how those plugins work and they are slightly different to eachother but they are both dynamic EQ's at their core, just with a tonne of different bands. I believe they have the ability to follow resonances around as they change frequencies, a bit like another plugin (Surfer EQ?). I think one of the tricks Gullfoss might use, or at least the mastering version of it, is to try and pull the sound more towards a pink noise profile. Then again, I might be confusing that with an iZotope plugin which does something like that..

This guy tries to remake popular plugins using some of the tools available in FL Studio. It gives you some pretty good insight into what these plugins are actually doing. Here's his attempt at making a Soothe 2 clone: https://www.youtube.com/watch?v=M8a5la4pz_g

[talby]

@Michael Willis did you meanwhile find a Linux plugin doing what you have been searching for, or got yourself such thing programmed?

[Michael Willis]

@Michael Willis did you meanwhile find a Linux plugin doing what you have been searching for, or got yourself such thing programmed?

My new saturation plugin has two stages of processing that accomplish what I was looking for:

1. I implemented a hysteresis effect that tames harsh high frequencies without doing a low pass filter. It allows low amplitude high frequencies through, but as the slope of the wave increases, the hysteresis effect reduces the slope, which ends up making the saturation sound more pleasant.
2. If #1 isn't enough, the EQ curve will do more. Note that the EQ only applies to the added saturation harmonics, and it does not impact the frequencies in the original signal.