Adobe Audition: converting very large number of aac files to mp3

[Steve233199797ly0]

I have about 40,000 aac files in my iTunes library. I need to convert them all to mp3 to make them playable by a digital audio player that does not support aac files. The library is about 350 total GB in size. Can Adobe Audition convert a batch that large? If not what can be done?

[Rag and Bone]

I guess you can try it and see.

Seems like an awful lot of files. I would certainly break it into smaller batches, since it seems that in 40,000 files some are going to have issues.

I guess you would just open up the batch window, select the files and run the batch. I don't know how much scratch space you need while the conversion is running, but I would make sure you have plenty.

[Steve233199797ly0]

Thanks for the response. I’m kind of scared to just go for it and see without having more to rely on. It’s a lot of files to either corrupt or lose.

S.

[Rag and Bone]

Seems unlikely ytou're going to corrupt them...the process shouldn't alter the original files.

[SteveG_AudioMasters_]

That's true about the original files - they won't get corrupted, but not really true about the copies: in order to do anything with a file that's not a wav, Audition has to decode it first so that it is a wav, and then re-encode it to the format you want it in. And that is destructive.

Leaving aside that you are going backwards in quality terms anyway (AAC was designed to be the superior replacement for MP3), there are supposed to be apps available that can do the transformation without decoding - at least that's what I've been led to believe. For more information in general about AAC look here.

I would certainly be somewhat reluctant to even attempt to use Audition for something like this, because it's going to take an eternity, what with all the decoding and recoding steps, so it's time-consuming as well. What's not so clear is how any of the available 'solutions' actually work - in terms of how they achieve this. I found a few listed here but they are all a bit non-commital about how they achieve the conversion. I'm a bit suspicious though - whilst the formats are not actually that different, I can't find any definitive description of how you'd go about this. What makes me even more suspicious is that many of the apps appear to let you convert them to a different stream rate - and that's definitely a decode/re-encode job.

So perhaps try a few, and see whether you're happy with the results. And then do a multiplication to work out how much of an eternity converting the lot will take!

[Steve233199797ly0]

Thanks very much Rag & Bone and Steve G!

It turns out I dont have to do the conversion after all. It was recommended by the store where I purchased an Astell Kern SK25 MK II DAP to play my itunes library. They said the new device did not support AAC.  I ended up setting iTunes to export in MP3 and just dragged the whole media file into the new device's hard drive. It did take a number of hours but in the end all the files ended up in the DAP as MPEG 4 files and the play just fine.

So problem averted!

Thanks again for weighing in.

[SteveG_AudioMasters_]

It did occur to me after posting that the ideal solution was probably to use a different export in iTunes. I presume (although this isn't stated clearly) that the files are actually stored in a non-compressed format in the iTunes server and compressed upon export to the format you want - in which case there's no extra degredation. Well, at least you've got a solution!