[LAU] Batch normalising wav files

[Jörn Nettingsmeier]

On 12/24/2010 02:53 PM, Q wrote:
> Hello
> 
> I'm wanting to batch process a bunch of wav files, normalising them all
> to -0.3 dBFS.

that's high! you will almost certainly get distortion in the analog
stages of cheaper playback equipment with a signal that hot. think
inter-sample peaks.

> I thought I could do this with normalize/normalize-audio, but it doesn't
> look to be possible. The man page suggests that simply analysing the
> file and raising the level so the loudest peak is 0 dBFS isn't
> normalising, which is news to me:

depends. that's peak normalisation. what you probably want is loudness
normalisation, which adjusts the levels so that the perceived loudness
is constant across tracks.

in a presentation i heard recently, the presenter played a metallica
single, in direct comparison to pink noise at full scale. the metallica
mix was significantly louder. go figure...

> " --peak
> Adjust using peak levels instead of RMS levels. Each file  will be
> adjusted so that its maximum sample is at full scale. This just gives a
> file the maximum volume possible without clipping; no normalization is
> done."

that is a funny definition of normalisation.

> That would be okay, except I want them normalising to something other
> than full scale.
> 
> Is there a quick and easy way to do this?

like julien suggested, use a standard peak normalizer and then attenuate
by 0.3dB )(if you are sure that's what you want to do).