Compression

A compressor is a device for automatically controlling the level of

an audio signal

Compression

The use of compressors can make recordings sound more

polished by controlling maximum levels and maintaining

higher average loudness.

Compression

Additionally, many compressors will have a

signature sound that can be used to add coloration and tone into otherwise lifeless

tracks.

Compression

If a ratio of 2:1 is set, an input signal exceeding the threshold by 2dB will be output with a level of only 1dB over the

threshold

It 'turns down' the audio when the level exceeds a threshold set by the user

CompressionTo make the effect of compression smooth and natural-

sounding, compressors often allow attack and release time parameters to be set by the user

attack release

The output control is used to restore the peak level of

the compressed signal to that of the uncompressed input

signal

Valve Compression

Valve (or Tube) compressors have a slower response than other forms of

compression. Because of this, they have a "vintage" sound that is nearly impossible to achieve with other compressor types.

Optical CompressionOptical compressors affect the dynamics of an audio signal through a light element and an optical cell. As the volume of an audio signal increases, the light element

emits more light, which causes the optical cell to lower the volume of the output

signal.

FET Compression

FET or “Field Effect Transistor” compressors emulate the tube sound with

transistor circuits.

VCA CompressionVCA or "Voltage Controlled Amplifier”

compressors use solid state circuits. They are usually cheaper than tube or optical

compressors. VCA's also tend to have less "colour" compared to optical or tube

compressors— similar to digital vs. analog tape comparison in recording.

Noise GatesA noise gate mutes the signal when it falls below a certain

threshold the rate or release time determines how slowly the

gate re-opens