[LAU] Batch normalising wav files

[Q]

Hi Julien!

Thanks for that, I might install those and give it a go.

Searching the net, there are many tools which say they normalise things 
but it turns out they're really intended for replay gain adjustments of 
recorded music -- it's possible they would normalise to a user-specified 
figure but I wouldn't lay money on it. Something from the audio 
(recording) ecosystem, like Eca, is what I was looking for.

As I understand it (i.e. from reading Katz) dB is meaningless without an 
indication of the reference point to which the ratio refers. In the 
analogue domain you get dBu and dBm with their own reference points.

In the digital domain that reference is the maximum encodable level, 
full scale, which is denoted as 0, hence everything is minus some level 
dBFS. I would have thought that for a program like Ecasound dB would 
have been (a lazy) shorthand for dBFS.

Thanks again

Q

Julien Claassen wrote:
> Hi Q!
>   Ecasound can do the trick, but in two steps, I'm afraid to say:
> for F in *.wav; do
>   ecanormalize $F
>   ecasound -i $F -o normalised$F -eadb:-0.3;
> done
>   You need ecasound and ecatools for that.
>   I think though, that -0.3DB seems rather hefty. Well there is a 
> difference between db and dbfs, have to look it up on Wikipedia.
>   Ecasound's version must be 2.7.0 I believe. Otherwise you can use a 
> different amplifier, which works in percentage of maximum volume:
> ecasound -i input.wav -o output.wav -ea:97
>   That is lower volume to 97% of the current volume.
>   Hope you can work with that. If not, well there's always csound and 
> its relatives, but that might really go a little overboard. :-)
>   Pianoly yours
>           Julien