Processing many mp3's

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hutzlibu
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Processing many mp3's

Post by hutzlibu » Thu Mar 22, 2018 10:51 am

Hey,

I have a big pile of (old) Audio Recordings(in MP3), that needs to be processed a bit.
So to each and all of files in a folder, there should be equializer applied.

And doing it all by hand ... sounds stupid, when Computers were invented because of automatisation ..

I just don't know, if Audacity is suitable for the task, as I only rarely used it for small tasks.
So it seems that you can operate audacity from the command line, which is maybe what I need to write my script?

viewtopic.php?f=21&t=99255

But it says experimental, so is there maybe already something stable, or maybe anyone has done something similar allready, or there is also some built in function for processing many files?

If not, I will probably give the method a try. But if it takes too long, I probably can also program the whole thing directly ... but I am doing it for someone else, and it would be probably easier for future task to learn about Audacity automatisation.

Anyway, thanks in Advance and thanks for Audacity in General :)

steve
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Re: Processing many mp3's

Post by steve » Thu Mar 22, 2018 11:03 am

Audacity 2.2.2 has "Chains": http://manual.audacityteam.org/man/chai ... ation.html

This feature will be replaced in the next version of Audacity with a much more flexible feature called "macros", but for your task, Chains may be sufficient.
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hutzlibu
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Re: Processing many mp3's

Post by hutzlibu » Thu Mar 22, 2018 11:40 am

Yes, this was exactly what I needed.
So looking forward to macros, as the Chains feature looks maybe a bit messy to do more complex stuff, but for just the equializer I needed, it is perfect.

Thanks a lot :D

kozikowski
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Re: Processing many mp3's

Post by kozikowski » Thu Mar 22, 2018 1:46 pm

And just when it looks like things are going well....

Audacity doesn't edit (or equalize) MP3. It sucks them into its own super high quality internal format and then makes fresh new MP3s when you're done. In other words, it doubles the MP3 compression distortion. If your source MP3s were already right on the edge of being ratty quality, the new ones may be officially ratty.

You can get around this completely by exporting the works in perfect quality WAV (Microsoft) or you can cause less compression damage by exporting in very high quality MP3 (stereo in 256 or 320 quality).

Archival masters in MP3 are not recommended.

Koz

hutzlibu
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Re: Processing many mp3's

Post by hutzlibu » Fri Mar 23, 2018 12:25 am

Ah yes, this I did suspect.
But the original quality of the old recordings were not that nice anyway, so it still sounds better after processing.
(and I allways use 320 nowdays...)

kozikowski
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Re: Processing many mp3's

Post by kozikowski » Fri Mar 23, 2018 4:00 am

(and I allways use 320 nowdays...)
Terrific. That's close to the ACX AudioBook submission standard.
Each file must be 192kbps or higher 44.1kHz MP3, Constant Bit Rate (CBR).
But they're in mono, not stereo. And it also says "or higher."

Koz

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