WAV versus MP3 formats

as a newbie, i keep seeing tips that recordings should be saved as WAV files for editing/mastering purposes, yet sites like ACX require MP3’s.

Is it safe safe to assume that we would save a recording as a WAV, then edit that WAV and export sections (chapters) as MP3s once editing is done?

Trying to understand the best way to format files in an optimal sequence.


ACX requires MP3 (at a very high quality/bitrate) because they’re a company and they have to store these things. Storage costs money and MP3 files are common and tiny. They picked MP3-Constant-192 as a submission standard because they can produce all their different products and services without having the sound quality get too bad.

Never do production in MP3. You can’t edit an MP3 and keep the quality constant. MP3, for the most part is a deliverable and listening format. Full Stop. There is no take an MP3 and do something with it other than listen.

It’s sneaky, too. Let’s say you did your announcing, editing, and correcting and export the work at MP3-192. That’s the ACX standard, right? Then you open it up later, Master it to reach the ACX sound standards, check it carefully, export a new MP3-192 and go home. That will fail submission. Two 192s one after the other is lower quality than 192. Even worse, your original edit masters can never be used to make a submission because whatever you do, the final is always going to be lesser quality than 192.

You have guaranteed you’re going to read it again from the beginning.

There are sneaky ways around this. The actual ACX standard is MP3 at least 192 quality. So you could figure out which two super high qualities one after the other come out better than 192. 256 and 320? 320 and 320? Don’t need to edit a chapter twice and then export for submission. That will almost certainly fail.

Or you could do all your work with WAV backups and edit masters and make the MP3 the last thing before you send the file off for publication.

WAV does have a quality number. I think it’s something like 1440 and it’s constant.


Having said all that, WAV files are not open-ended either. Because of internal housekeeping, Audacity makes very slight changes to the WAV shows it exports. They’re not perfect. But they’re a shining beacon on the hill compared to the way MP3 does it.