K2 - Peak Compressor
Posted: Mon Dec 26, 2016 10:14 am
Hi all,
Following the 'K1 RMS compressor' I'd like to share with you the next example, this time a PEAK compressor.
K1 RMS compressor:
http://www.dsprobotics.com/support/viewtopic.php?f=3&t=5976&p=28462#p28462
As discussed on the former thread (K1 Compressor) any compressor needs an ED (Energy Detector) to activate its 'Side chain' or 'gain computing channel'. These can be divides into RMS or PEAK based.
RMS based ED's mimic the way that the human ear perceives SPL changes and is good for 'normalizing' tracks, flatennning the SPL changes between different sources and overall SPL control. An RMS detector is designed to ignore short peaks, causing the whole compressor to 'miss them out' (for good or bad).
A PEAK detector is designed to catch these short peaks, so naturally it is more recommended for controlling fast transients and specific instruments (drums, kicks, plucks). Peak compressors also serve better for De-Essing tasks.
The design itself is based on the following article (already mentioned on this forum):
https://www.eecs.qmul.ac.uk/~josh/documents/GiannoulisMassbergReiss-dynamicrangecompression-JAES2012.pdf
K2's ED is designed as a 'smooth peak detector', placed in the log domain, just after the TF (Transfer function). See the article itself for more details...
For me, it was very interesting to run both designs (K1 and K2) on similar musical material and audition how they act completly different. I invite you to do the same and share with us any interesting findings.
I do plan to share the code itself, once more mileage is done with this design.
{next steps: GUI design with sliders, Wet/Dry knob, Look ahead buffer}
Please do send your remarks !
Rocko
Following the 'K1 RMS compressor' I'd like to share with you the next example, this time a PEAK compressor.
K1 RMS compressor:
http://www.dsprobotics.com/support/viewtopic.php?f=3&t=5976&p=28462#p28462
As discussed on the former thread (K1 Compressor) any compressor needs an ED (Energy Detector) to activate its 'Side chain' or 'gain computing channel'. These can be divides into RMS or PEAK based.
RMS based ED's mimic the way that the human ear perceives SPL changes and is good for 'normalizing' tracks, flatennning the SPL changes between different sources and overall SPL control. An RMS detector is designed to ignore short peaks, causing the whole compressor to 'miss them out' (for good or bad).
A PEAK detector is designed to catch these short peaks, so naturally it is more recommended for controlling fast transients and specific instruments (drums, kicks, plucks). Peak compressors also serve better for De-Essing tasks.
The design itself is based on the following article (already mentioned on this forum):
https://www.eecs.qmul.ac.uk/~josh/documents/GiannoulisMassbergReiss-dynamicrangecompression-JAES2012.pdf
K2's ED is designed as a 'smooth peak detector', placed in the log domain, just after the TF (Transfer function). See the article itself for more details...
For me, it was very interesting to run both designs (K1 and K2) on similar musical material and audition how they act completly different. I invite you to do the same and share with us any interesting findings.
I do plan to share the code itself, once more mileage is done with this design.
{next steps: GUI design with sliders, Wet/Dry knob, Look ahead buffer}
Please do send your remarks !
Rocko