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Audio files for non-audiophiles
March 1, 2009 9:27 PM   Subscribe

What is the simplest way (free or otherwise) to convert M4P and M4A audio files to MP3 en masse?
posted by fusinski to Technology (13 answers total) 5 users marked this as a favorite
 
Side note: Platform preference is Windows.
posted by fusinski at 9:28 PM on March 1, 2009


iTunes will do this - but keep in mind, every time you convert a file, you degrade the audio. Don't be surprised if it starts to sound mushy - especially if you're not converting to a high bitrate.
posted by 2oh1 at 9:50 PM on March 1, 2009


I assume any of the major-ish Windows media playing programs will do this, provided that you have LAME installed. Unless they're copy-protected, in which case you would first need a program to strip off the copy-protection.
posted by sinfony at 10:08 PM on March 1, 2009


Ignore the bizarre name of this program: Akme FFmpeg. It just works. Perfectly.
http://sourceforge.net/projects/akmeffmpeg/
posted by Gerard Sorme at 10:13 PM on March 1, 2009


M4P is the protected DRM format. Legally speaking, you aren't suppose to convert to a different format. At one point there was an easy way to do this. I haven't looked around for this "solution" for a few years now as I haven't been using an iPod in awhile.

As for the .m4a files, iTunes will do it for you. I recommend at least 2x the bitrate of the original file. Even at max bitrate you will still lose some of the audio quality. Whether or not you'll notice the degraded audio quality due to transcoding between formats will depend on how sensitive your ears are and how good your audio equipment is.

Just out of curiosity, is there a specific reason you want to convert the files? If it is due to a particular software music player that doesn't support the .m4a file format, you might want to look into an addon called 3ivx which I think should add support to most Windows based music player apps.
posted by nickerbocker at 10:56 PM on March 1, 2009 [1 favorite]


I use Hymn to losslessly decrypt .aac-.m4p files to .m4a. Then dBpoweramp Reference (totally free and unrestricted 21 day trial, $36 to buy) to convert to mp3. Has a nice batch converter. I'm not a shill, I have paid for this software, worth every cent in my opinion.
As noted above, you will lose some sound quality in the transcode to mp3. Doesn't bother me, although my hearing isn't up to scratch anymore.
posted by Duke999R at 3:12 AM on March 2, 2009


myFairTunes
posted by ezekieldas at 7:58 AM on March 2, 2009


Just out of curiosity, is there a specific reason you want to convert the files?

A friend of mine just bought a new vehicle which has an MP3 player (w/ hard drive) built in. He has a lot of tracks purchased via iTunes and are, yeah, in the protected m4p format. I am not going to judge him for whatever legal gray area he's mucking around in. :) He just mentioned that he has found a couple solutions himself, but none of them preserve the tag information. I'll have him check out akme and myFairTunes.

This morning I found a pay-to-play app called TuneClone which seems to burn your m4p files to a virtual CD and then to MP3... anyone have experience with this?
posted by fusinski at 8:09 AM on March 2, 2009


One could, I believe, pay the iTunes Music Store to "upgrade" the Fairplay-DRM-encrusted files to 256kbps, non-Fairplay, AAC files, which one could convert to MP3 in iTunes itself.
posted by andrewraff at 11:10 AM on March 2, 2009


Is all content available as 256kbps iTunes Plus files?

NoteBurner is similar to TuneClone, and the same price ($34.99 USD). There's a wiki-how and eHow for using this, though it seems really simple. Virtual CD does the same, with possible issues. There are a few other such programs, all around the $35 USD pricepoint.

LifeHacker has an article on DVDneXtCOPY iTurns Free, and some users mentioned Requiem, which is found only via P2P programs, as there's a constant battle between Apple and the Requiem programmer. I still haven't tried it out, but it's fairly easy to find. Another program mentioned in the comments is DRM Media Converter, though the page makes me wonder about the program quality and safety (the download is free, but costs $40 to do what?)

Googling about further turns up a LOT of programs with the same set of features, and all $20-40 USD. I think they may all be based on the same core elements, possibly some open source package.
posted by filthy light thief at 11:36 AM on March 2, 2009


Yeah, I noticed that Googling did net a lot of results, which is kind of why I asked. A lot of those packages look extremely questionable to me, and I was hoping to figure out which were vehicles for spyware without becoming a victim via testing.

Thanks for all the help, everyone.
posted by fusinski at 11:50 AM on March 2, 2009


As far as M4P files are concerned - burn them to CD, reimport into iTunes and then convert to MP3.
posted by highrise at 12:15 PM on March 2, 2009


highrise - the problem is that it would take a while (and many CDs) with a large collection, and you might not get all the tags back easily. And you're still re-encoding lossy files. At a certain point, paying for a DRM decrypter and re-encoder would be cheaper than the used media and time involved.
posted by filthy light thief at 8:56 PM on March 2, 2009


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