Is "compression" essentially a volume (gain) change?

[skyfly]

Is "compression" essentially a quick volume (gain) change?

 

[abdo123]

not really, it's like cropping a portion of a picture and then zooming that portion to get the original size.

 

[skyfly]

not really, it's like cropping a portion of a picture and then zooming that portion to get the original size.

I guess that will result in harmonic distortion, quite large amount.

 

[Oukkidoukki]

In a way yes. It compress the volume peaks in the signal. So you get more even volume level output. If you whisper and then yell to mic in the recording, it is hard to adjust volume in home stereo when listening. You are scared of the loud parts. With compression you are safe, sound output level is more even.

 

[Apesbrain]

What kind of "compression" are you talking about? If dynamic compression, it is making the loud parts softer while making the quiet parts louder. It is not a simple volume change.

https://en.wikipedia.org/wiki/Dynamic_range_compression