128K or 320K audio quality

For the most part, it's a personal decision - or unless you have really good equipment.

Personally, I have files ranging from 128k to 320k and it's not always easy to hear any difference. But since you got the 60GB and you're not worried about space issues, I would encode at 320K.

Depends. If you are only going to listen to your files on your ipod then 128 is probably fine. The difference comes when you take that 128kbps file and burn it to a CD (or play it directly) through a nice home audio system. Then you will definitely be able to tell a difference.

I did some tests using my own equipment at home and found that anything ripped at 256 and above was indistinguishable to me from the CD when played through my home stereo system (note this is purely subjective).

When I did the same test with my 3G ipod and stock headphones, I found that most music sounded great at 192 or above but I could definitely tell the difference between 128 and 192.

192 is a good middle ground that sounds perfect through small headphones and still stands up very well when put through a high end audio system.

Basically, if you have the free space, rip at 320, why not? If you have some space issues, go with 192. This is of course if sound quality is your top concern. If 128 sounds fine to you though, that's all that matters - go with it.

If I remember correctly (not at my home computer so I can't exactly look), songs downloaded from iTunes are encoded at 128 AAC, using (somebody correct me if I am wrong) Apple-lossless encoding. This helps keep the file size low while the quality remains hight.

I'm fairly certain that if you were to listen to the same song twice - once downloaded from iTunes and the other ripped from a CD at, say, 320K, I don't think you find a noticeable difference.

It just depends on how you encode your music files - .wma, .mp3, .m4-something (the iTunes encoding - don't remember the exact file extension). That is what determines quality/file size.

And all of that adds up to it being a personal prefernce thing. If you're worried about space and super-quality isn't a concern, go with a lower bitrate. Though anything lower than 128k sounds AWFUL - though I have been able to put small clips of mp3s encoded at 56k on my cell phone and they sound good through those speakers.

lossless encoding produces big files. Not as big as WAV files but still pretty huge. But I don't believe that ipod supports any lossless codecs. Am I wrong?

Note that when I spoke of 128/192/320 in my post, I was talking about MP3s. iTunes files are AAC (which is MP4). AAC gets you somewhat better sound quality at the same bitrates (especially lower bitrates).

Simon,

As Wes pointed out, I was incorrect when I referred to AAC as lossless. Those are two different codecs. AAC (which is mp4 as opposed to mp3 as Wes pointed out) is the format that iTunes downloads come in, and they are 128. But, because they're using a different codec than strick mp3s, they are able to have similar (or better) quality at lower bitrates. That results in similar (if not smaller) file sizes.

And yes, you can encode in AAC using iTunes, but most people don't do it because your average CD-burning program (Windows Media Player, Roxio EZ CD Creator, Nero, etc) doesn't (?) recognize AAC files to use for burning. Also, iPods are the only mp3 players that will play AAC files (once again, correct me if I'm mistaken), so that is why most people rip their CDs as mp3s instead of using AAC.

But you can do both of those (plus at least one or two other formats) using iTunes.

I hope that has cleared things up for you. I know it's help make things a little clearer for me.

I use 320k (54GB in Ipod) and can tell the difference on my excellent home audio system. In an Ipod it is overkill.

Unfortunately my 60GB model is going back as I have audio dropouts on 10% of songs. It is not the MP3 files as the dropouts are not repeatable and the songs sound fine using Itunes.

Don

I recommend these settings in iTunes:

AAC Encoder set to custom.

Stereo Bit Rate : 192 kbps
Sample Rate : Auto
Channels : Auto
Check Mark in : Use VBR

http://static.flickr.com/29/54682922_e122218bc8.jpg?v=0

I find these settings have both the quality I was looking for and a size that wont use or take up much room on an iPod.

judged by expert listeners to be “indistinguishable” from

well, apple invented AAC so they would say that. 8~P There are lots of unbiased real worl codec comparisons out on the net that can provide many hours of reading, but my experience is that 128 on a high end system does not sound as good as the original CD.

But that's my ears. Best way to tell is to test with yours. 8~)

128k Versus 320k should be like night and day, unless you're an idiot.

128k will sound washy, thin and gross.

320k should sound very close to original CD quality.

Don't use Joint Stereo as it mucks with the stereo imagery. I wouldn't recomend to 'Cut below 10Hz' and there's no point in using VBR with 320k.

Get a good pair of speakers if you can't hear the difference between 128 and 320.

Thanks for the link! Still have to say it all depends on what you like in the end, what sounds good to you the listener and the system you will be playing on the most. I imported the same track in all the formats iTunes offered and that is how I came to chose my settings. Everyone should experiment in the same way and try to pick what they hear as sounding good to them.

That link provides some interesting information but an important point to keep in mind is that the listening comparisons the writter performed were not blinded. That IMO makes the conclusions highly suspect. As he mentioned, you can get some measure of "blinding" by using the shuffle feature (which I have tried) but the problem is, the volume levels of the various files to be compared are not necessarily the same. That too pretty much invalidates any comparisons as the louder file, even if just a slight bit louder, will tend to sound better.

My ears aren't as young as they used to be but I've performed a lot of comparisons and I don't believe I can tell the difference between 128 kbps (MP3 or AAC) and WAV so Apple's claim seems legit to me.