Tweaking filter envelopes

The Lounge General Discussion
1

I’m trying to learn more about how to get interesting evolving sounds sculpted with the filter. Wondering if there are some go to settings for the filter envelope ADSR. So far I can tell the attack makes a big difference, but what about the other settings and how to best match that with the amplitude envelope or some LFOs.

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To answer your question in detail would take more than a short reply. But I try, nevertheless … to keep it short :wink:

I would say the following parameters define a particular tone in the following order of importance (IMO of course):

  1. cutoff position
  2. resonance position
  3. envelope of the cutoff
  4. modulation depth of the envelope of the cutoff
  5. envelope of the resonance, if available (most synths don’t have it)
  6. envelope of the VCA

Let’s have a look on the attack phase only and using a resonant LP filter:

  • If the attack is very short, the tone will just jump quickly to maximum brightness.
  • If the attack is long and no resonance is set, the tone will move from dull to brighter, but nothing spectacular there,
  • If there is a decent amount of resonance set, there will be some kind of “whooping” and,
  • the “whooping” will become more articulated, if the attack is followed by a similar decay, which is useful for “funky”-like sounds, as an example.

The VCA makes the tone more or less loud only, but cutoff and resonance make the character of the tone.

More examples:

  • If you’re after a “bowed string”-like sound, it’s best to have slow attacks for VCF and VCA.
  • If the sound shall be more “plucked”, short attacks are needed for both.

But there is no need to have the envelopes for VCF and VCA identical. Sometimes it’s much more interesting to have quite different envelopes.

An example: “punchy”-sounds:

  • both attacks of VCF/VCA should be quite short,
  • but I often set a longer decay for the ADSR of the VCF, a fitting decay, and near to zero sustain, and
  • a very short decay for the ADSR of the VCA, a 50%-75% level for the sustain, and
  • nearly the same release for both

With this settings the sound is at the beginning very loud and bright compared to the decay/sustain phase, which gives it a strong and prominent transient at its start.

IMO the best understanding will develop by DIY. I would suggest to create some slow, moderate, and fast sequences or arpeggios and then take some good time and tweak:

  • cutoff-starting frequency (makes quite a difference starting low or high)
  • the modulation depth of the cutoff (this makes a big difference!)
  • various levels of resonance
  • various ADSR for VCF and ADSR

A LFO can be used in so many ways … we can use it to wobble something, we can use it to get some fluctuation, be it syncronized or more random, we even can use “single-shot” LFO modes to add an additional envelope … there is so much to explore …

And don’t forget … have fun … and make music :wink:

8 Likes
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Great answer, exactly what I was looking for, thanks!

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You’re welcome. Glad to read that this made sense to you :slight_smile: