Go Back   Cockos Incorporated Forums > REAPER Forums > newbieland

Reply
 
Thread Tools Display Modes
Old 12-03-2019, 05:34 AM   #1
read
Human being with feelings
 
Join Date: Apr 2015
Posts: 1,378
Default compression question again (release)

PLease confirm if this is true or not "the compression still works and compresses even when the signal falls below the threshold"

if not...i don't see and can't understand why release would be doing anything to the signal

if yes please further explain so i can understand

thank you
read is offline   Reply With Quote
Old 12-03-2019, 05:48 AM   #2
Xenakios
Human being with feelings
 
Xenakios's Avatar
 
Join Date: Feb 2007
Location: Oulu, Finland
Posts: 8,062
Default

Yes, the compression (that is, gain reduction) will still be active when the signal goes below the threshold. The release time determines how quickly the signal below the threshold goes back to its original level.

This image shows what's going on with a 440Hz sine wave that has a sudden increase and decrease in its volume, going through ReaComp :



Just as a tip : It's useful to use sines or other very simple signals as inputs to better see what is happening with various processings.
__________________
I am no longer part of the REAPER community. Please don't contact me with any REAPER-related issues.
Xenakios is offline   Reply With Quote
Old 12-03-2019, 06:06 AM   #3
read
Human being with feelings
 
Join Date: Apr 2015
Posts: 1,378
Default

Quote:
Originally Posted by Xenakios View Post
Yes, the compression (that is, gain reduction) will still be active when the signal goes below the threshold. The release time determines how quickly the signal below the threshold goes back to its original level.

This image shows what's going on with a 440Hz sine wave that has a sudden increase and decrease in its volume, going through ReaComp :



Just as a tip : It's useful to use sines or other very simple signals as inputs to better see what is happening with various processings.
thanks Xenakios

whats one reason we would like to keep compressing below the threshold? i.e long release time?

why there's any such thing as compressing below the threshold when we set the compressor to work only above a threshold in the first place
read is offline   Reply With Quote
Old 12-03-2019, 06:19 AM   #4
Xenakios
Human being with feelings
 
Xenakios's Avatar
 
Join Date: Feb 2007
Location: Oulu, Finland
Posts: 8,062
Default

Quote:
Originally Posted by read View Post

why there's any such thing as compressing below the threshold when we set the compressor to work only above a threshold in the first place
The compression (gain reduction) can't just be suddenly stopped when the signal goes below the threshold, that would cause a click in the sound. The same is true if you would be doing manual volume automation, very sudden changes in the volume envelope can cause clicks/pops in the sound. Of course these things are not necessarily easily audible with "real life" signals.
__________________
I am no longer part of the REAPER community. Please don't contact me with any REAPER-related issues.
Xenakios is offline   Reply With Quote
Old 12-03-2019, 06:25 AM   #5
read
Human being with feelings
 
Join Date: Apr 2015
Posts: 1,378
Default

Quote:
Originally Posted by Xenakios View Post
The compression (gain reduction) can't just be suddenly stopped when the signal goes below the threshold, that would cause a click in the sound. The same is true if you would be doing manual volume automation, very sudden changes in the volume envelope can cause clicks/pops in the sound. Of course these things are not necessarily easily audible with "real life" signals.
so this statement is true?

the compression still pushes the level down (even if its lower than the threshold) until the release stage has been completed.

this will help me understand better
much appreciated Xenakios
read is offline   Reply With Quote
Old 12-03-2019, 06:30 AM   #6
Xenakios
Human being with feelings
 
Xenakios's Avatar
 
Join Date: Feb 2007
Location: Oulu, Finland
Posts: 8,062
Default

Quote:
Originally Posted by read View Post
so this statement is true?

the compression still pushes the level down (even if its lower than the threshold) until the release stage has been completed.
When the signal goes below the threshold, the release stage starts ramping the gain back up to the original level. (So it's not a constant gain reduction during the release stage.)
__________________
I am no longer part of the REAPER community. Please don't contact me with any REAPER-related issues.
Xenakios is offline   Reply With Quote
Old 12-03-2019, 06:41 AM   #7
read
Human being with feelings
 
Join Date: Apr 2015
Posts: 1,378
Default

right, thank you!
read is offline   Reply With Quote
Old 12-03-2019, 11:36 AM   #8
ashcat_lt
Human being with feelings
 
Join Date: Dec 2012
Posts: 7,272
Default

Realize also that the actual instantaneous level can go below the threshold hundreds or thousands of times each second. Attack, release, and RMS time help to smooth that out. With all three at 0 you have waveshaping/distortion.
ashcat_lt is offline   Reply With Quote
Old 12-03-2019, 05:18 PM   #9
DVDdoug
Human being with feelings
 
Join Date: Jul 2010
Location: Silicon Valley, CA
Posts: 2,779
Default

Quote:
whats one reason we would like to keep compressing below the threshold? i.e long release time?

why there's any such thing as compressing below the threshold when we set the compressor to work only above a threshold in the first place
Depending on the particular compressor and the sound you want, you can set very-short release times. When working with files (i.e. not in real-time) it's even possible to have "look ahead" and negative attack or release times.


Limiting is a special kind of compression with very-fast attack & release.
DVDdoug is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -7. The time now is 04:22 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.