Music format question.

[Kristenn]

I was told AAC 128kbps stereo sounds better than MP3 320 kbps stereo so I converted my library over. But instead of using AAC high quality at 128 kbps I used iTunes Plus at 256 kbps. I was wondering if bumping AAC down to 128 kbps would make a huge difference in sound quality?

I know it will save space on my iPod and make the hard drive spin less often which will also save iPod battery life. But if it will dump sound quality I don't think its worth it.

So does AAC 128 kbps really sound as good as MP3 @ 320 kbps? I stopped using MP3 a long time ago because its a space hog >.>


Thanks in advance ^^

[Galley]

The higher the bitrate, the better the audio quality. They say 128Kbps AAC sounds as good as 192Kbps MP3. Converting a lossy file to a lower bitrate will result in an even worse sounding file. You may not like the sound of 128Kbps AAC; try 192Kbps, instead.

[Kristenn]

Thanks ^^

Converting to that now. As long as it sounds good and saves as much space as possible, I'm happy.

Gotta haves my movies

[Jolly Jimmy]

Don't convert between lossy formats like mp3 or AAC! Each time you do so the sound will just get much worse. I hope you have backups of your mp3s before you transcoded them.

[enberg]

Originally Posted by Kristenn

I was told AAC 128kbps stereo sounds better than MP3 320 kbps stereo

You were told wrong.

[dXTC]

Originally Posted by Galley

The higher the bitrate, the better the audio quality. They say 128Kbps AAC sounds as god as 192Kbps MP3. Converting a lossy file to a lower bitrate will result in an even worse sounding file. You may not like the sound of 128Kbps AAC; try 192Kbps, instead.

Seconded. Most of my collection is in 192. You would indeed have been disappointed in 128.

That said, if I had a Classic, I'd re-encode what I could at 256, with a handful of my fave tracks in Lossless. I'm much more of a music fan than movie fan. Your priority apparently is shifted a little more toward movies, so 192 is perfect in your case.

Originally Posted by Jolly Jimmy

Don't convert between lossy formats like mp3 or AAC! Each time you do so the sound will just get much worse. I hope you have backups of your mp3s before you transcoded them.

Usually I would recommend that, but some people are satisfied enough with transcoded files, as long as the source is of high enough bitrate that most of the original audio signal is still there. IMHO, 320Kbit qualifies for this, for non-audiophile users.

[ChrisA]

Originally Posted by Kristenn

So does AAC 128 kbps really sound as good as MP3 @ 320 kbps? I stopped using MP3 a long time ago because its a space hog

Of course not.

AAC sounds a little better than an MP3 of the same bit rate.

But if you trans-code from one format to the other you loos quality no matter what. If you want to change from MP3 to AAC to have to re-rip the CD. Transcoding gives you the worst of both.

[spice weasel]

I'm voting for 256 kbps AAC, which I think sounds really good on headphones.

But one thing to keep in mind is your future listening needs. If you only plan on ever listening to your music on inexpensive headphones attached to an iPod, then 256 will be fine. If you ever want to listen to your music on nice home stereo speakers or high-quality headphones, however, you might want to consider Apple Lossless. The downside, of course, is that it takes up a lot more storage space, meaning you can't sync as much to your iPod. To get around this, I just sync my iPhone regularly, and swap out the artists that I want to listen to for the next few days. On the plus side, you have an aurally-exact copy of your CDs, and you can re-encode them to newer and better codecs in the future without any loss in quality. It's future-proofing your digital music.

[roebeet]

As others have mentioned, once you have a lossy source (be it AAC or MP3), you should never transcode it again as the sound quality will suffer no matter high high the target bitrate is.

That being said, I believe the general rule of thumb is that AAC SQ is usual comparable to the next bitrate up, for MP3. So, a 160kps AAC would be comparable to a 192kps MP3, assuming they were transcoded from the same lossless source.

[Kristenn]

Hmm. In that case I will just keep it at 256 kbps. My iPod isn't near full yet and I hate the idea of sacrificing the sound quality of the music for movies I could swap out anyway.

Thanks for the replies!