Key Tracking Filter [Finally!]

Post Reply
User avatar
Logickin λ
Posts: 73
Joined: Sat Sep 08, 2018 8:31 pm

Key Tracking Filter [Finally!]

Post by Logickin λ »

I just realized that I keep saying the word Tracking Filter, for a few topics.

But there are disadvantages:
- particularly paraphonic
- not the most efficient solution
- not able to use tracking filter
- it has the worst case when all notes are triggered at a different time, result in not achieved the number of voice as requested
- really nerdy (involved too many logic circuits), too complicated to create another set of synth
- take too many modules (can be replaced with a metamodule though)
When I was making MetaModule synth, I always hope for the MetaModule can received Audio and Midi at the same time. This is important since we can design more compact tracked filter or something crazy like using audio signal to import MetaModule patches or making modules able to communicate each other.

- So... Where is your filter? I never see you make one.
People would properly ask this question.

I made a key tracking ADSR while back, but it was based on my old DigitalSoundwave ADSR which uses 2 analog generators to create an envelope. The module is not a successful product and I never use it much. It has a few problems and limitations:

- Outdated mechanism, due to the use of my old, orphaned, inefficent and limited ADSR module.
- The Cutoff is flawed. Setting the cutoff to 100% does not give you clean, "un-filtered" signal.
- The Cutoff envelope intensity is not as exciting as the normal Filter cutoff we found in vst plugins
- The amount option is done by setting the base and the ceiling of the cutoff frequency, which is confusing.
- The release stage is actually missing
and there are many more problems...

But Now! I can safely say that I have finally solved most of them!
Introducing... The Key Tracking Filter!!!

This filter makes use of the pitch2ctrl and finding the base of the cutoff frequency, then apply a number of multiples to get the ceiling of the cutoff frequency which is used for limit the peak of the ADSR given the pitch. Through a number of trial and error, finally getting the intensity of the ADSR, EG amount, and the cutoff curve right, result in an exciting cutoff fading experience.

Thanks to the discovery of the delay as an input which use can not passing audio and midi at the same time. The Key Tracking Filter is now in a single module, instead of having 3 parts. (Key tracking ADSR + Sound2Control + Filter pro)

To use the module, simply connect to your favorite synth as audio and multiSynth as midi in to the Key Tracking Filter, or you can connect from my "2nd Order Kasplus-Strong" or "OP-Block" (Will be release in future, since there is a note freeze bug currently) which has a midi output already. Once the setup is done, you can use the Filter out of the box!

Here are some examples:
DO NOT use the modules in the DEMO, as they have bugs and missing features!
Demo 1 shows how to set up of the module, behavior of the module which is paraphonic and "Last note tracking", and maintain the same harmonic content with different pitch including gliding notes:
Key tracking filter mk3 Demo
(13.85 KiB) Downloaded 23 times

Demo 2 shows the cutoff behavior with different amount setting, which is crucial for music in EDM category:
Key tracking filter mk3 Demo
(14.01 KiB) Downloaded 22 times

And here is the module.
Logickin Key Tracking Filter Mk3.3.5.sunsynth
(23.85 KiB) Downloaded 26 times

Have Fun! If there is a problem, please comment down below.
I was stressed out by my own matter, but I am finally back on the SunVox discord.

My sound cloud:
My Audius:
Post Reply