Compression - what is it and how to use it

[tomana]

came across a nice, easy to read and too the point write up on Compression (courtesy TC Electronic) and thought I'd post it for those who view compression as a no-go zone. Next to having auto-compression (such as the TC Helicon Mic Mechanic has) the following is about as simple as it gets. There are more complex Compressors out there with more than the standard four controls for those who love to spin knobs

Here's what I did to overcome :

I bought a Used pro level Compressor (if you can find a Used Boss CL-50 for under $200 grab it because you've just hit gold and it has a superb noise gate as well). Pop on a set of headphones, plug it into the Compressor output and have at it - play around with the controls. It wont take time

Introduction

A compressor is used to reduce the dynamic content of a signal. How can this improve your guitar’s appearance in the overall sound? There are situations where a compressor should not be applied – and there are definitely situations when it is the key to letting your guitar stand out and appear rock solid. Here are a few examples

Let’s say your aim is playing a steady clean rhythm guitar figure at the same level all the time. As we are all only human, this is virtually impossible: You cannot avoid playing a few strokes too hard once in while. This will most likely result in the sound engineer backing off a bit on the guitar channels in live situations to avoid harsh sounding peaks. At this “lower” overall level (that neither you nor the sound engineer intended in the first place), your weakest strokes in the guitar rhythm figure will now disappear completely

The best approach in this situation is using a compressor. When set correctly, it will reduce the highest peaks, giving you and the sound engineer a much more homogeneous guitar level to work with. You can also apply compression to a lead sound to “even out” level variations. Combine a low threshold setting (which allows the compressor to operate constantly) with a high ratio setting to achieve a very audible compression effect

Compressor Controls and what they do



Threshold
When the signal is above the set Threshold
point, the Compressor is activated and the gain
of any signal above the Threshold point is
processed according to the settings of the
Ratio, Attack and Release parameters

Ratio
The Ratio setting determines how hard the
signal is compressed (see illustration above).
Example: With a Ratio setting of 2:1, an input
signal at 4 dB above Threshold is reduced to
only 2 dB on the output side. The “Infinite”
setting gives you a Limiter function

Attack
The Attack time is the response time of the Compressor.
The shorter the Attack time, the sooner the Compressor
will reach the specified Ratio after the signal rises above
the Threshold point

Release
The Release time is the time it takes for the Compressor to release
the gain reduction of the signal after the input signal drops below
the Threshold point again

Gain
Use Gain to compensate for the level changes caused
by the applied compression

[clintj]

Thanks for posting that. That's easier to understand than quite a few articles I've found. I just got a fully adjustable rack mount one to play with for recording, that may get drafted into my PA as a peak limiter for those few extreme transient sounds - I've got a lot of power on tap and a bad feedback squeal can be deafening. Or maybe some subtle use on vocals, or whatever uses we find that sound good during practice.

[Villamarzia]

Originally Posted by tomana

if you can find a Used Boss CL-50 for under $250 grab it because you've just hit gold and it has a superb noise gate as well

Really? I would not even consider buying a compressor but if Boss CL50 is so good I could consider it.. On a local craiglist there are at least 4 pieces for sale in excellent conditions and all below 50$...

[RockerDuck]

An optical compressor is what I use. Its subtle like its supposed to be and doesn't kill the dynamic of your playing. This is for live use of course. Studio is a whole different ballgame.

[pitner]

I have two on my pedalboard a HBE CPR by Homebrew Electronics and a JB2 Janglebox. The CPR is my go to and I just leave it on as it adds sparkle and sustain to my sound for both electric and acoustic. The JB2 is more over the top think Byrds 12 string Rickenbacker kinda sound. Use the JB2 only with the electric and only some electric sound good with it. Mainly my tele and gretsch duo jet.

[tomana]

Originally Posted by pitner

I have two on my pedalboard a HBE CPR by Homebrew Electronics and a JB2 Janglebox. The CPR is my go to and I just leave it on as it adds sparkle and sustain to my sound for both electric and acoustic. The JB2 is more over the top think Byrds 12 string Rickenbacker kinda sound. Use the JB2 only with the electric and only some electric sound good with it. Mainly my tele and gretsch duo jet.

Quote:
That kind of stacking was the first thought to come to mind for Agnello and Hamilton as well: “As far as time constants, you could put on a very slow, low-ratio compressor first, and send that into a fast limiter that’s catching just the top of the peaks,” said Hamilton. “That can make it feel like the track is plowing through molasses to get to the limiter. With that approach, you can take something that’s very lightweight and stringy, like an arpeggiated nylon-string guitar, and get some real heft out of it. It’s almost like adding a sense of inertia; some real weight in a mix.”
End Quote