Compression

[Hot Tub]

I'm physically cringing as I type this. Could someone please tell me what compression does? I've heard and read a lot of talk about using compression to get a particular sound, but when I try to use it the only thing that happens is that things get loud enough to make small children cry. In Norway.

So, what's it about? Is it just a means of preventing damage to the input stage of an amplifier, or to a speaker, or does it actually change the sound?

Sorry, I know it's a really dumb question, but it's bugging me and I can't understand much of the stuff on the net.

[Musky]

[url="http://basschat.co.uk/index.php?showtopic=337"]http://basschat.co.uk/index.php?showtopic=337[/url]

[NancyJohnson]

[quote name='Astronomer' post='187650' date='Apr 28 2008, 10:23 PM']I'm physically cringing as I type this. Could someone please tell me what compression does? I've heard and read a lot of talk about using compression to get a particular sound, but when I try to use it the only thing that happens is that things get loud enough to make small children cry. In Norway.

So, what's it about? Is it just a means of preventing damage to the input stage of an amplifier, or to a speaker, or does it actually change the sound?

Sorry, I know it's a really dumb question, but it's bugging me and I can't understand much of the stuff on the net.

[/quote]

+1.

For me, limited compression evens out my bass so everything sounds [i]level[/i]. Excess compression c/w a bit of drive/gain gives me what Line 6 would describe as pawnshop punk/JJ Burnel kind of distorto.

To be honest, for some time I've been wondering what compression does as well...

P

[jakenewmanbass]

Don't cringe, I've been playing 30 odd years and I can't give you a full technical answer.
I think it pretty much does the job of pushing a sound to the front of a mix by evening out the performance, compensating for variations in loud and quiet depending on the setting you have. It can certainly give an added punch to bass notes, make it feel more compact, and in the mix can be used to add gain or keep a lid on notes that pop out.
Hope that makes sense, I'm sure you'll get some very good answers from the guys here.
Jake
PS over use can lead to a pulsing sound in the mix

Edited April 28, 2008 by jakesbass

[jakenewmanbass]

[quote name='Musky' post='187662' date='Apr 28 2008, 10:34 PM'][url="http://basschat.co.uk/index.php?showtopic=337"]http://basschat.co.uk/index.php?showtopic=337[/url][/quote]
Now[i] I [/i]didn't know that was there, so thanks to the OP for asking and Musky for pointing it out.
Asking was a good move

Edited April 28, 2008 by jakesbass

[Hot Tub]

[quote name='Musky' post='187662' date='Apr 28 2008, 10:34 PM'][url="http://basschat.co.uk/index.php?showtopic=337"]http://basschat.co.uk/index.php?showtopic=337[/url][/quote]


THANK YOU!

I'll try to digest this, and probably come back with more stoopid questions!

Cheers!

[budget bassist]

It makes the really loud stuff a bit quieter and the really quiet stuff a bit louder.... basically.

Actually i may have to see if i can get myself one... the difference in volume between fingerpicking and slapping drives me nuts sometimes, i might get a noise gate too.... hmmm

Edited April 28, 2008 by budget bassist

[Cantdosleepy]

[quote name='Astronomer' post='187650' date='Apr 28 2008, 10:23 PM']I'm physically cringing as I type this. Could someone please tell me what compression does? I've heard and read a lot of talk about using compression to get a particular sound, but when I try to use it the only thing that happens is that things get loud enough to make small children cry. In Norway.

So, what's it about? Is it just a means of preventing damage to the input stage of an amplifier, or to a speaker, or does it actually change the sound?

Sorry, I know it's a really dumb question, but it's bugging me and I can't understand much of the stuff on the net.

[/quote]

There's no reason to cringe. We're all born knowing nothing (probably. Maybe. Depending on who you ask) and we all have to ask questions to learn stuff. If anyone gives you gyp then they're are a big meanie.

What everyone else says. You set the threshold and the ratio on most compressors. Any sound louder than the threshold is squeezed quieter according to the ratio you've chosen. Means that super-loud sounds don't stand out so much, and you can raise the volume of the quiet bits.

Lots of contention exists about the amount you should use it, but most of the controversy surrounds using it on a whole song at the mastering stage - if you make the loudest bits and the quietest bits the same volume and superloudify everything, where are the dynamics etc etc?.

Bit of compression on the bass can work a treat.

[charic]

dammit you all beat me to it... what they said

[BOD2]

[quote name='budget bassist' post='187720' date='Apr 29 2008, 12:16 AM'].... i might get a noise gate too.... hmmm[/quote]

Make sure you understand what a noise gate can and cannot do before you buy to avoid disappointment.

A noise gate monitors the signal level. When the level drops below a threshold value (set by you) the gate "closes" cutting off the signal from your bass. When you play a note the level rises above the threshold and the gate "opens" letting everything through.

In practice a noise gate will only remove noise when you stop playing notes. As soon as you play the gate opens and it's as if it wasn't there.

So, if you're hoping the noise gate will remove noise WHILE you are playing, it won't. In a live setup it only really makes a difference in between songs (i.e. when you stop playing). In recording it can help to reduce noise in quieter passages when you stop playing.

You also have to be careful setting the threshold to avoid the undesirable effect of the natural decay of sustained notes being killed off as the signal level drops below the threshold and the gate closes.

[Cantdosleepy]

Indeed. There's a great example (as in, obvious and audible) of a noise gate on Godspeed You Black Emperor's version of Hungover as the Queen in Maida Vale. The guitar part is noisy when playing notes, but in the silences between the hum just drops out:

[url="http://www.imeem.com/dopplganger/music/2aLRPhzo/godspeed_you_black_emperor_hung_over_as_the_oven_in_maida/"]http://www.imeem.com/dopplganger/music/2aL..._oven_in_maida/[/url]

It's also a bangin' tune!

[bassbloke]

The downside to compression is that too much of it can rob your bass of any dynamics and character, introduce hiss and boxiness to your sound and allow you to become a sloppy, inaccurate player.

I've really gone off compression recently. I now just use a bit of limiting on my sound to rein in any harsh peaks.

[cheddatom]

limiting is compression though, and quite an extreme form of it. It's just easier to set a limiter to be subtle.


RE Bod - I need to use a noisegate to stop my rig from feeding back due to the insane amount of dirt/fuzz/compression and volume going on, so while it's not noticable, it deffinitely does more than just cut me out between songs.

[ped]

Limiting is very different to compression, there is a thread about it somewhere.

[cheddatom]

[quote name='ped' post='187954' date='Apr 29 2008, 12:07 PM']Limiting is very different to compression, there is a thread about it somewhere.[/quote]

If I get a compressor, and set the ratio to infinite, and set the attack to instant, then I have a limiter. Am I wrong?

[ped]

Hmm too early for all this. I think you would get a limiting effect but the limiter will not affect the quiet sounds or change the sustain of notes at all. BOD2 is an expert on this, so I bow to his, and possibly your greater knowledge!

I always used to use a limiter rather than compression, I disliked the seasick sound and liked having a definitive bottom clank which a limiter gives. However I now use an XT pro and the compression on the front panel is just fabulous, much more musical and more subtle than anything I have tried. I guess weather you like it or not can depend heavily on what bass, compressor and rig you have. So difficult to say, really!

[cheddatom]

[quote name='ped' post='187967' date='Apr 29 2008, 12:22 PM']Hmm too early for all this. I think you would get a limiting effect but the limiter will not affect the quiet sounds or change the sustain of notes at all. BOD2 is an expert on this, so I bow to his, and possibly your greater knowledge![/quote]

A limiter wont affect quiet sounds, unless you set the threshold very low.

Compression/limiting doesn't actually give you more sustain, but it makes it seem like the notes are holding longer because the attack portion of the note is quieter, and so the sustain portion will be louder in comparison.

[bremen]

[quote name='cheddatom' post='187956' date='Apr 29 2008, 12:09 PM']If I get a compressor, and set the ratio to infinite, and set the attack to instant, then I have a limiter. Am I wrong?[/quote]

You're absolutely correct...you don't have to set the attack to instant though, the definition of a limiter is a compressor with (approaching) infinite gain reduction over threshold. It's still a limiter if it's got a slow attack, though limiters are mostly used with fast attack.

[BOD2]

Compression and limiting are very similar. A compressor with the ratio set to inifinity will certainly "limit" the output. Where it all gets confusing is the available controls on your compressor. If you can set the attack to "instant" (some pedal compressors don't have enough user controls to do allow this) and not apply any "make up gain" then this would allow the compressor to work fully as a limiter. So I suppose it depends really on your compressor.

But note that true limiting only works at the loud end of the signal spectrum - all it does is stop your signal exceeding a preset level (usually for the protection of equipment or to prevent overload somewhere along the line). Unlike a compressor, a limiter will not bring up the quieter parts of the signal so it has a slightly different application.

[bass_ferret]

Many amps have a limiter in the output stage so you dont destroy cabs, Peavey's DDT being the most obvious example. This can be why your volume does not increase as you turn the master up - all you are doing is increasing the signal cut out by the limiter.

Slapping/tapping/funk fingers etc, more dynamic techniques benefit most from compression as it evens out the sound as described above.

[cheddatom]

[quote name='BOD2' post='187978' date='Apr 29 2008, 12:32 PM']But note that true limiting only works at the loud end of the signal spectrum - all it does is stop your signal exceeding a preset level (usually for the protection of equipment or to prevent overload somewhere along the line). Unlike a compressor, a limiter will not bring up the quieter parts of the signal so it has a slightly different application.[/quote]

well, you're talking about standard applications. If I have a limiter and set the threshold very low, then it will be effecting the quieter notes. If the limiter has a make-up gain control then........

yeh, it's just different names for the same thing IMO.



Another point - Don't you wish all compressors had attack controls! God knows why they make pedal compressors with 3 knobs that you can't do much with.

[ped]

That makes sense, thanks for clearing it up...