FLAG (free) Oppressor (Multiband Ducker/Compressor)

Hi All,

I just released my fourth module in my free plugin. This is more experimental.

It is a multi-band ducker, or a spectral-ducker… the frequencies of the “key” input will attenuate the corresponding frequencies in the “main” input.

Suggested use-cases include:

  1. Get rhythmical ducking by having percussion as key, and sustained notes (chords, bass) as main
  2. Unmask a solo instrument by “oppressing” supporting elements (chords, arpeggios, riffs, cymbals)

The name is inspired by “Aphex Dominator”… I always loved the “over-the-top” names for effects. So this one is called “Oppressor”.

If the “key” input is un-connected it will use the “main” input and function like a simple multiband compressor. The vu-segments will turn red in this mode.

Each vu-meter-segment represents one dB of attenuation.


  • SENSE, adjusts the “sensitivity”
  • RANGE is how deep a frequency will be cut. It defaults to 6dB and goes btw. 0dB up to 12dB.
  • A (Attack) is how fast the dampening will “kick in”, set it to low values for rhythmical effects.
  • R (Release) is how fast the dampening of the frequency will go away (half-life).

Omri recorded a great video showcasing it here:

(note: this video was made before I added attack, and before vu-segments)

I put together a short clip too here:

And this:

Thanks, Jonas


Welcome to the spectral frequency manipulation club! :smiley:

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Tack Jonas! It seems do a pretty clear job, tried yesterday with simple sidechain from kick drum. But definitely need to try more expressive frequency content in the Key input.

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That’s pretty cool. It’s pretty clean, too!


I updated Oppressor:

  1. Added “attack” parameter
  2. Meter show decibels.
  3. Changed meter from bars to vu-segments (one decibel per light)



Very nice module this - reminds me a little of the Trackspacer VST

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Jonas could you add a polyphony to all your plugins?

I have thought about it… and I’m yet to be convinced…

I tend to get a lot more use out of polyphonic modules than mono but less so with signal processing stuff. There are quite a few sequencers, for instance, that I would get more use out of if they could be made poly (though that is not always easy).

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one of the whole points of modular synthesis is easy access to all the parameters. (first one to admit that lots of Eurorack modules have abandoned this).

As soon as you make a module polyphonic, you now have to either (1. assume parameters affect all the channels or (2. introduce some kind of menu diving or other UI hack to access each channels parameters.

Both these options suck, which is why I completely understand Jonas’ reluctance


Yeah… for some stuff it makes a lot of sense… like for cv and gates I kind of get it.

To me, polyphony works really well for midi. And you can visualize it with fingers pressing piano-keys.

But, for instance if/when I make a stereo-version of the ensemble module I’ll introduce some tasteful cross-channel interaction. The same for the multi-tap delay.

The way I think it would make sense is to imagine a mono-module as “cloned” under the hood… and the controls automatically connecting to each instance… but that is not very powerful…

Polyphony wouldn’t really fit multi-channels application where the signals carry something useful… like “left” and “right”… or “sub” or “center channel”…

Rant over…

I often just make a stereo version with the same settings in both sides. Testers always ask for that, so that’s why my “Shaper” and “Stairway” are stereo. “Saws” pans the saws left to right. I think even @almostEric makes many of his modules stereo.

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ok. And could you make some kind of makeup compensation for Oppressor if you’re interested it of coure?

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You mean like makeup gain for compressor-mode (red lights)?

Yeah I thought about it… it would make sense… I’d like to avoid new knobs though, so I could probably calculate the gain based on the range knob.

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MixMaster would like a word with you. :wink:

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Unless I’m mistaken the poly in mixmaster is carrying multiple mono channels… the output is still stereo… and the panning is only left-right. So it would still fit in my “multiple mono” mind-model

(edit) I guess the direct-out and returns are stereo-pairs… I guess to clarify what I meant was that they have “hard coded” these inputs as left-right-pairs… you can’t get a “surround” channel by adding a third channel in your poly-cable.

yep. My “Comp” compressor is “stereo”, and each of the two channels can be 16 channel polyphonic. But - Mind Meld users tell me that having all the channels with the same setting won’t cut it for channel insert usage.

Make sense… I like the “fat cable” idea… and I’ll probably use it, but only for “simple” stuff.

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Hi @VCVRackIdeas, the new version (v1.3.2) has makeup gain in the compressor-mode… the makeup is based on the range knob. Try it out!