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LMMS / lmms

Cross-platform music production software
https://lmms.io
GNU General Public License v2.0
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Harmonic filter #3022

Open unfa opened 8 years ago

unfa commented 8 years ago

The idea came to me when thinking about simulating drum resonance.

For kicks and snares I use a standard resonant HP filter for that - I cut off unwanted low-end and boost the drum body resonance, giving more thump to the drum sound.

However - I realized that the resonance is not just one band - it should be a series of bands creating a harmonic series. But that's not esy to do with simple peak filters - you'd need to stack them, and calculate frequencies and gains for good simulation, and changing the frequency would require a ton of manual work.

Why not make a special filter unit that creates a harmonic (or inharmonic if the user wants) bank of bell (peak) filters that tune automatically to harmonic frequencies of the fundamental filter frequency picked by user? This could be also a harmonic notch filter as well - creating comb-like efects but in a different and much more controlable fashion -because one could for example change the harmonic to inharmonic with automation.

Just an idea. What do you think?

PaulBatchelor commented 8 years ago

It sounds like you want a filter bank of some sort, but I'm a little unclear about what would be automated?

PaulBatchelor commented 7 years ago

@unfa Modal synthesis comes to mind, which is used most often in physical modelling of sounds. Typically you feed some sort of excitation signal into a filter bank of modal resonators, which are tuned to match resonant properties of real world materials. This sort of effect was implemented inside of csSpectral for the iPad.