mp3 or aac

[staka69]

I have about 76gigs worth of MP3's but I'm thinkning of converting them into aac files to throw in my new 20 iMac I bought a few months back, plus that would give me a little extra room on my 60 gig iPod.

I would still keep my original hard drive with the mp3 format just in case I did not like the way aac's sounded.

My question is, we (my workplace) just purchased a quad 2.5 ghz power mac with 1 gig of ram. I want to use that as my machine that does the conversion cuz it can probably do it much faster than my intel iMac or XP machine at home. Any ideas how many hours that may take, the reason I ask is cuz I want to come into work on a Saturday or something and hope it's done by Sunday so nobody notices I used the quad 2.5 mac for 'non work' related purposes.

Thanks,

Mike

 

[Soulstorm]

If you convert the mp3 files to aac, the files will have much reduuced quality. The only way to achieve maximum quality possible with aac is to convert the ORIGINAL songs (from aiff) straight to aac. This happens because when you convert a song to mp3, some information gets lost permanently. So, when you reconvert them, no matter what format you convert the song into, more information will be removed, resulting in very poor quality.

As for the quality of mp3 and aac:
AAC in 128kbps sounds almost like an MP3 in 192kbps. That's not the only parameter you must take into consideration, though. In mp3, the information that is removed from a song, concerns the quality of the drums or other frequencies like that. In AAC, the information that gets removed concerns the quality of the bass.

Anyway, you can perform a test on your own: Try converting an AIFF file to mp3 first. Then, convert the aiff file to aac. Compare the 3 files and see for yourself the difference.

Note that there are differences between converters: Use LAME for mp3 conversion. It is slow, but guarantees the best quality in 160-192kbps. On the other hand, AAC is better than MP3 in 128 kbps. But that impression may be subjective.

Try for yourself and see what you like the most.

 

[staka69]

Thanks for the tips

 

[TrenchMouth]

I whole heartedly agree, do not convert your mp3 files!

However, if you are going to do it anyway...and you can overcome the hurdle of getting 76gigs of music onto the quad, have it convert to acc, and then move the resulting sum of files to the desired location, without someone finding out, well then i encourage you to do it just to be all sneeky like. Its not like you are doing anything that bad...

If I could make an educated guess...I think you would be cutting it real close in one night. With a very rough math based guess, it would take my 1.33ghz iBook about 144 hours to convert 76 gigs of music...Now, I know those quads are fast, but.....

I say go for it, just for the fun of it. But i dont think you are going to care for he sound quality that much.

If i use aac i like to rip at 160kbps with vbr on, and if its mp3 i like it at 192k with vbr. im not that picky, but pickier than some.

my .02 Good Luck.

 

[iBunny]

I convert all my music from CD into AAC 320kbps. I may not be able to tell the quality with the speakers I have, however, I want to have the highest quality with the best compression just in case.

so 320Kbps AAC is good to go.

 

[jdechko]

I convert all my music from CD into AAC 320kbps. I may not be able to tell the quality with the speakers I have, however, I want to have the highest quality with the best compression just in case.

so 320Kbps AAC is good to go.

True, I do the same with my CD's. But he's going from MP3 to AAC which will suck to begin with as far as quality loss. Also, he has 76 gigs and wants to fit it down (I supposed) onto a 60 GB iPod, so he needs to move to a smaller file.

To the OP; I second Soulstorm's recommendation that you re-rip them to AAC as the quality will be much better. But if you can't go to AAC 128, as it's probably your best bet (as long as the bitrate on the original MP3 is greater than 160).