I am an idiot??

[camn]

call me stupid... but I keep hearing this phrase:

"6db of comression at a 2:1 ratio"
(or however many at whatever ratio..)

and I ... in my infinite knowledge.... have NO IDEA what it means? I dont set my compressors to deliver a certain number of dbs of comp.... what does it mean??
Does it mean set it so that.... peak level minus threshold level quantity divided by ratio equals 6 (or howevermany) dbs of Compression??


what, in gods name, does it mean!!?? (BTW.. I know what the RATIO part means!)

xoxo

ps.. new record's done!! due out next month!

[dobro]

Camn - Ed's got it right.

But whether that 6 dB of gain reduction is in relation to peaks or average level... well, that's another story.

[James Argo]

Deffinitelly... what can I say ?




...kiddin', gotcha !!!!

[Ethan Winer]

Camn,

Below is a brief explanation of compression you may find useful.

--Ethan

====================

A compressor or limiter is an automatic volume control that reduces the volume when the input gets too loud. Originally they were used to prevent AM radio transmitters from distorting if the announcer got too close to the mike. Then some creative folks discovered that a compressor can sound cool as an effect on voices and musical instruments. The primary controls on a compressor are:

Threshold - also called ceiling - This sets the point at which the automatic volume reduction kicks in. Below that volume the compressor does nothing. When the input gets above that level, the compressor reduces the volume automatically to keep the signal from getting much louder.

Attack time - how quickly the volume is reduced when the input exceeds the threshold. If it's too slow, then a short burst of loud music can get through and possibly cause distortion. So when using a compressor as a tool to prevent overload you generally want a very fast attack time. But when used on an electric bass to get a little more punch, 20-50 milliseconds is often good because that lets a little burst of the attack get through before the volume is reduced. So each note has a little extra "definition" but without the full length of the note being too loud.

Release time - how quickly the volume comes back up after being reduced. If it's too fast, you'll hear the volume as it goes up and down. That sound is called "pumping" or "breathing." Sometimes this sound is desirable, but often it is not. It depends on whether you're using the compressor as a tool to prevent overloading, or as an effect to create a cool sound or add more sustain to an instrument. If you don't want to hear the compressor work, set the release time fairly long (one second or more).

Compression ratio - 1:1 does nothing. 2:1 means if the input rises to 2 dB. above the threshold, the compressor will reduce the level by 1 dB. so now it's 1 dB. above. 10:1 means you have to get 10 dB. above the threshold for the output to go up by 1 dB.

[amt7565]

Nice post Ethan. Concise and clear

[camn]

I still dont get it.

It's not really that I dont get what it means... but what do people mean when they say it??

so check me...Like.. if my peak is, say -10... and someone says "put 5db of comp on"....I can do this..

a) thresh=-20 ratio 2:1

OR

b) thresh = -25 ratio = 3:1

OR

c) thresh = -30 ratio = 4:1

?????????

Which, indeed.. all sound different?!

If this is true... and someone says "put 5db of comp on"... do I Immediately ask... "what ratio?"

oh.. and am I supposed to just always know the peak values of the SHITE Im mixing??

thanks, ed!

xoxo

[littledog]

You're no idiot camn.

Simply talking about 5dB of compression without any other parameters is ambigous, as you pointed out.

If you do hear someone talking about 5dB of compression, maybe they are talking about limiting, because in that case a high ratio and short attack time are assumed.

[Shailat]

It really depends on the result you want as ...saying "put 5db of comp on".... is really useless unless they explain to what degree.

A typicall reduction of 5dB would mean that at the strongest section of your track there should be that amount of compression. And so you set the threshold to get that amount be it whatever....that is compression which is considered the most natural and audio wise should be affective but not to obvious to the fact that you have used compression.

Had they meant limiting then they should say so and not compression....Anything different should be explanied to you exactly what they want.

[Scott Tansley]

I am an idiot??

camn, I told you that a year ago, remember. But thats when I was an idiot. Remember. Now where both idiots.

[camn]

ah. Very good. Very good!

xoox

[RWhite]

Camn - I'm looking forward to the new record!

[Son of Mixerman]

Originally posted by camn
call me stupid... but I keep hearing this phrase:

"6db of comression at a 2:1 ratio"
(or however many at whatever ratio..)

Its been awhile since I tried to explain it and I may botch it but here it goes.


6db of compression with a 2:1 ratio means something is usually peaking 12db past where the threshold is set at? I always try to view it as fractional, i.e. 1/2 of the peak gets compressed, 1/3rd of the peak...past the threshold. 2 in 1 out, 3 in one out... 4:1, 12db peak gives you a 3db reduction or 1/4th of the peak.

RMS is more musical because its an averaging of the overall material. So compression typically will have lower ratio's when using RMS. The Attack is how fast the compressor pulls the trigger to compress the signal and release is how long it take to let go once the signal drops below the threshold. Sometimes the problem is when people like me use slang when trying to convey something technical.

Sorry if I blew it in trying to explain it, Im left handed

SoMm