Reson~ changing Q with constant output volume

mudang's icon

Hi all,

I'm looking for a formula to compensate the volume loss, when raising the Q factor of reson~ bandpass filter.

The input signal is noise-like (brushed snare).

Any ideas?
A heuristic formula would be sufficient.

Thanks a lot!
Jan

Peter McCulloch's icon

Q = center frequency / bandwidth (in Hz)

Compare the previous bandwidth to the current bandwidth and that's probably a starting point for a ratio. (Previous:current)

Alternatively, you could use an envelope follower, convert its output to db via atodb~, and apply makeup gain.

mudang's icon

Thanks Peter!

The solution was to simply multiply the output signal with the Q factor!
The overall volume is not perfectly constant but good enough for my purposes.

Cheers,
Jan