Audio files very low quality when exporting as m4a

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fuegotakis
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Joined: Mon May 03, 2021 9:38 pm
Operating System: Windows 10

Audio files very low quality when exporting as m4a

Post by fuegotakis » Mon May 03, 2021 9:55 pm

I was editing an m4a file, and when i exported it as m4a, the audio quality of the output file was really bad, a lot worse than the original file. The windows explorer properties menu says the original file is 320 kbps and in the export menu, I also selected 320 kbps. The output file also shows as 320 kbps in windows properties, however as I said, the quality is very obviously a lot worse than the original file when listening.

DVDdoug
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Re: Audio files very low quality when exporting as m4a

Post by DVDdoug » Mon May 03, 2021 10:03 pm

That's odd... M4A/AAC is supposed to be immune to "accumulated compression damage". (MP3 is one of the worst with repeated encoding, but even with MP3 one extra generation of MP3 encoding shouldn't make it "terrible".)

What kind of editing/processing did you do?

fuegotakis
Posts: 3
Joined: Mon May 03, 2021 9:38 pm
Operating System: Windows 10

Re: Audio files very low quality when exporting as m4a

Post by fuegotakis » Mon May 03, 2021 10:26 pm

DVDdoug wrote:
Mon May 03, 2021 10:03 pm
That's odd... M4A/AAC is supposed to be immune to "accumulated compression damage". (MP3 is one of the worst with repeated encoding, but even with MP3 one extra generation of MP3 encoding shouldn't make it "terrible".)

What kind of editing/processing did you do?
All I did was cut part of the audio, and add a fade out at the end.

DVDdoug
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Re: Audio files very low quality when exporting as m4a

Post by DVDdoug » Tue May 04, 2021 12:33 am

I have no explanation.

There are a few M4A editors that can do simple editing like cutting/fading without decompressing but I don't have one so you'll have to search. MP3directCut (which I do have) is supposed to handle M4A (without decoding) if you add a DLL but I couldn't get it to work.

fuegotakis
Posts: 3
Joined: Mon May 03, 2021 9:38 pm
Operating System: Windows 10

Re: Audio files very low quality when exporting as m4a

Post by fuegotakis » Sun May 09, 2021 3:44 am

could it have something to do with the file itself? since i know the file was originally an mp3, and was changed to m4a by someone else

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