REACOMP parameters?

[RAMI]

Hey,

REACOMP has a "Pre-Comp" parameter. What is that? The obvious answer seems to be that it's to set how long the compressor will take before it kicks in on a signal. But I thought that's what the "Attack" control is for, and it has both.

Wut be up wit dat sheeznit.

 

[diggy_dude]

I don't know, but the parameter name suggests a look-ahead value in samples or milliseconds. Some digital compressors take an advance look at the signal so the attack can be anticipated.

 

[RAMI]

Could be. For what it's worth, the parameter value is in ms., so you may be right.

 

[diggy_dude]

I just had a look at that. There's no mention of it in the Reaper Manual. The "Classic Attack" control needs some explaining as well. I suspect these controls all interact in some way.

 

[RAMI]

I just had a look at that. There's no mention of it in the Reaper Manual. The "Classic Attack" control needs some explaining as well. I suspect these controls all interact in some way.

Yeah, I agree. "Classic attack"? Isn't a millisecond a millisecond? Or were they shorter in the 70's?

I also stumbled upon something else while trying to figure it out. If you hit the "UI" button, it changes the whole look of the plug-in and it gives you a lot more parameters that you don't see in the other view.

 

[diggy_dude]

Yeah, it does that for all of the effects. Notice the "Classic Attack" changes from a checkbox to a slider in that view too.

 

[RAMI]

it does that for all of the effects.

Interesting. I had no idea. I wonder if the default view isn't the one we should be working with.

 

[diggy_dude]

Well, the default view has the meters and more logical control groupings. I suppose the alternate view would save some MIPS due to the meters not having to be re-rendered in realtime.

 

[d.bop]

I think I can help

Pre-comp is a look-ahead option and will start compressing the signal x milliseconds before the signal actually reaches the compressor. As for classic attack: I believe it has a different attack shape than the default and is there for compatibility with older projects from before ReaComp was updated. Pipelineaudio can probably give more info on this, though..

The UI button is on all plugins and will switch to a generic view as if no UI had been coded in the plugin to begin with (for example: the Simulanalog suite.) I'm not positive on this either, but my guess is that this is also there for compatibility. Probably as a way to still access the plugin's controls if the graphics glitch up.

 

[RAMI]

I think I can help

Pre-comp is a look-ahead option and will start compressing the signal x milliseconds before the signal actually reaches the compressor. As for classic attack: I believe it has a different attack shape than the default and is there for compatibility with older projects from before ReaComp was updated. Pipelineaudio can probably give more info on this, though..

The UI button is on all plugins and will switch to a generic view as if no UI had been coded in the plugin to begin with (for example: the Simulanalog suite.) I'm not positive on this either, but my guess is that this is also there for compatibility. Probably as a way to still access the plugin's controls if the graphics glitch up.

Thanx man,

So, if I understand it correctly, when the "Pre-Comp" is engaged, the "Attack" probably has no effect. It just seems that it would be counter-productive to have the compressor "looking ahead" the way most limiters do, but still having to wait for the attack time. Sounds like it would be a stale-mate.

 

[diggy_dude]

All digital effects work with a set of adjacent samples, not just a single sample. Maybe the pre-comp just increases the window size or something.

 

[DaleVO]

Your question got me curious and digging through the Reaper manual too.

Here is an explanation that I found in the Reaper forum:
http: (forward slash twice) forum.cockos.com/showpost.php?p=484159&postcount=14

Hope it helps.
D

 

[d.bop]

Your question got me curious and digging through the Reaper manual too.

Here is an explanation that I found in the Reaper forum:
http: (forward slash twice) forum.cockos.com/showpost.php?p=484159&postcount=14

Hope it helps.
D

Good find!

That link reminds me of these posts:
Cockos Confederated Forums - View Single Post - How to use a Compressor
Cockos Confederated Forums - View Single Post - How to use a Compressor
Great visuals!

These links also show what ReaComp's "Classic Attack" looks like

 

[DaleVO]

You too d.bop, good find! Saw those posts in my search.
Those additional graphics really make your's and diggy's explanations clear and helped this newb wrap my mind around the usage of the comp/pre-comp.
D

 

[aaronmcoleman]

Pre comp seems to be a look ahead. It doesn't seem to make much difference. I think it just makes sure the attack is exactly 20ms, or whatever value youve chosen. It's more precise.

I think classic comp is a program dependent attack and release like an 1176. So the threshold, and ratio will determine the attack and release. That's what it sounds like to me when I use it.

 

[pipelineaudio]

Pre comp is as suspected a lookahead. To get a really REALLY good feel for how it works, put ReaComp on a sustaining track like a distorted guitar

Set the guitar track to 4 trackchannels and set ReaComp's detector to aux input

Send a send from a kick drum or snare drum track to trackchannels three and four of the guitar channel

Set ReaComp's attack and release to zero and ratio up pretty high

Turn the threshold so that the drum is ducking the hell out of the guitar

Start ctanking up the pre comp and notice how the guitar ducks before the drum even gets hit

 

[aaronmcoleman]

Oh, interesting. That makes sense now.