Re: [SoX-users] Process too soft/loud audio with sox

[Eric W. <nor...@yh...>]

Francesco Ariis <fa...@ar...> wrote:
> Hello sox-users,
>     I have an audio file which is at times too soft and at times too
> loud. I would like to make the soft parts a little bit louder and the
> loud parts a little bit softer.
> 
> Can sox do this?

compand and mcompand can do it in sox natively.  They're a bit
tricky to learn but fmiser wrote some great posts:

https://sourceforge.net/p/sox/mailman/message/23427259/
https://public-inbox.org/sox-users/200...@gm.../

For simple cases or a final pass after compand/mcompand; I like
tap_limiter from the TAP-plugins LADSPA package:

	sox $IN $OUT ladspa -lr tap_limiter -4 3.5
	(limit to -4dB, add 3.5dB gain)

	http://tap-plugins.sourceforge.net/

I usually use compand or mcompand for recordings which need a
lot of correction.  tap_limiter is good for recordings which
only need a little correction, or after everything else (EQ,
compand/mcompand, etc...)