Is 128kbps AAC enough?

March 31, 2005 9:05 AM

Do you think that 128kbps AAC files are good enough?

I was checking out the Apple Music store (for the first time), and was actually very surprised on what kind of selection they had, and their prices are hard to beat (are they?). The DRM bothers me, but not too much as there are ways around it if need be. I'm use to buying audio CDs and ripping them as ~196-256 vbr mp3s. After they are ripped I package up the CD (unless I want to read the booklet) and put it away in a box and really don't ever pull it out again. Thinking an Online Music store would probably be better for me, but how close will the sound quality come to what I'm use to? 128kbps doesn't seem like enough for something I payed money for.

posted by nickerbocker to Computers & Internet (19 answers total)

I usually rip CD tracks as 196kbps MP3 files, and I can't discern any difference in quality between those and the iTMS tracks that I've downloaded. I'm no audiophile, but I listen to a lot of music on my Mac, and on my iPod, and for me it's never been an issue.
posted by veedubya at 9:09 AM on March 31, 2005

Its not an issue for me either.

Granted most of the stuff that I import / Download is usually only used on my IPOD with mediocre headphones, or my computer, even worse speakers.

The sound quality is probably going depend on how you listen and what you expect to hear.

Your best bet is probably just to import some songs you already know well at a lower level and see if you can notice a difference.
posted by szg8 at 9:20 AM on March 31, 2005

128 Kbps AAC sounds much better than 128 Kbps MP3.
posted by kindall at 9:38 AM on March 31, 2005

I rip at 192 aac but that may be overkill.
posted by TetrisKid at 9:48 AM on March 31, 2005

I agree with kindall. That said, I find that 128 AAC tracks can sound very thin and compressed. The bass in the AAC tracks does sounds much better than an MP3 using the same sampling rate, but it doesn't come close to CD quality for me. Through lower-end headphones or an iTrip it's not too bad, but I really notice the difference when I'm streaming using Airport Express or listening with the Etymotic ER-4Ps. I've actually been ripping at 256 AAC which I'm sure most people will say is overkill.
posted by anathema at 10:07 AM on March 31, 2005

anathema : I won't say it's overkill. I rip at 320 MP3 because I listen to my iPod either through my high-end stereo or headphones.

If you're using standard headphones 190 would be best if you're dealing with classical music because violins do the audio equivalent of a moire pattern at lower levels most of the time.
posted by Vaska at 10:24 AM on March 31, 2005

I don't think they're good enough, but, per szg8's suggestion, the best (maybe only) way to find out for sure is to perform some blind tests on yourself. (And kindall, as far as I know, is right--every listening test I've ever seen suggests that 128k aac sounds better than 128k mp3).
posted by box at 10:26 AM on March 31, 2005

The best reason not to buy from the iTunes music store is that, because the files are lossy compressed, you'll never be able to convert them to another format without losing quality. That's a good enough reason to say they're not good enough.
posted by ascullion at 10:29 AM on March 31, 2005

A rule of thumb amongst my AAC-using friends is that you can basically step down a notch from MP3 for the most part (ie: 192 CBR MP3 down to 160 AAC) without noticing any difference. I've got a couple of friends who, after doing some blind testing in their normal audio listening environments (none of us writes for any audiophile magazines or has a >$1000 stereo, mind you) have decided to rip everything at 128 AAC and have never looked back. In my own listening environments, I can't tell a difference either.

I'm not sure, but I am under the impression that you cannot do VBR AAC without paying for QuickTime Pro, or, presumably, some non-Apple encoding software, but I would think that VBR AACs between 128-160 would be at least fine for most songs and most computer-based listening. I haven't gone this route, but if I'd had a few extra dollars the last time I ripped my music collection (which probably will be THE last time I rip my music collection), I probably would have done it this way. *Possibly* 160-192, but I have a "just in case" mentality.

Finally, the only place I know that can beat the iTMS is allofmp3.com, but I think that's best described as a "grey market."

On preview, ditto what others are saying about testing your own music for yourself. It's the best way to be certain!
posted by kimota at 10:30 AM on March 31, 2005

The iTMS previews are meant to be exactly the same quality as the real thing, so you should be able to judge for yourself.
posted by cillit bang at 11:18 AM on March 31, 2005

The best reason not to buy from the iTunes music store is that, because the files are lossy compressed, you'll never be able to convert them to another format without losing quality.

Is this correct? I was under the impression the loss of quality happened when the files were transcoded from the source material to .aac, and that assuming a method of unlocking Apple's DRM, perfect copies and conversions could be made with no further loss of quality. But you're saying that, say, an .aac converted to an .aiff would lose fidelity? Wouldn't the .aiff just be a perfect copy of the imperfect .aac?
posted by jbrjake at 12:42 PM on March 31, 2005

I think what ascullion meant is that you'll never be able to convert them to another lossy format without loss of fidelity. You could certainly dump the audio from an AAC to an AIFF or WAV file without losing any of the quality from the AAC file, but converting that AIFF or WAV file to an MP3 (or other lossy compression format) would incur an additional drop in quality.

Additionally, I've always been quite happy with my 128 Kbps AAC files, both ripped into iTunes directly from CD and purchased from the iTunes Music Store.
posted by esd at 12:55 PM on March 31, 2005

I ripped my old CD's as 320 Kbps MP3's and I only buy music from AllOfMP3.com because they give me 320 Kbps MP3's.

I can hear the difference between 320 and 128.
posted by exhilaration at 12:58 PM on March 31, 2005

I play my tunes through my home theater system. I have a hard time discerning between the quality of tracks I ripped myself (eithe 160 cbr of 192 cbr) and tracks I've downloaded from iTMS.

I can, however, tell the difference between straight CD audio and ripped music.
posted by pmbuko at 2:03 PM on March 31, 2005

As everyone else says, download a few and listen for yourself. I've found that 128kbps AAC isn't good enough for me - but, then, neither is 128kbps MP3. I usually go for 256 or 320 kbps MP3s, myself, and I can certainly hear the difference between relatively high quality stuff like that and 128kbps AAC or MP3, particularly on stuff like classical music. So it seems plausible to me that you might hear a difference as well, given the bitrates you say you usually rip at. I do think that AAC is a little overrated... it might be better than MP3, but I haven't found it to be the vast increase in quality that everyone else seems to find it. [Shrugs] Either way, it doesn't ultimately matter whether the rest of us think it sounds decent - listen yourself and decide whether it's OK for you.
posted by ubersturm at 2:23 PM on March 31, 2005

jbrjake: Lossy formats strip different frequencies than one another and use different algorithms. Let's say out of a frequency scale of 1 to 10 that MP3 strips 2 and 10 and AAC strips 4 and 5... now you're missing 2,4,5, and 10....

Read this at the FAQ at OGG Vorbis (my preference) about transcoding MP3's to OGG.
posted by trinarian at 2:35 PM on March 31, 2005

Response by poster: Thanks for all the replies. I have heard samples of different songs at different compression levels, and I really can't hear the difference beyond 128kbps AAC files on my current equipment. I don't own >$1000 equipment, but I might some day. So I'm just worried when I get to the $1000 equipment some day will I think my purchased files sound like crap... I guess that is what I'm getting at. I wish that iTMs would allow you to re-download purchased songs, and they offered at least 192kbps AAC files.
posted by nickerbocker at 5:28 PM on March 31, 2005

I've definitely noticed some issues with 128kbps AAC I've ripped when compared to the source in the form of weirdness with cymbals and other high frequency sounds. I've noticed similar glitches with a few purchased tracks as well.

I wish Apple would get ahead of the curve and make higher quality encodings an option. Right now, I'll buy one or two tracks from a given artist or album from iTMS, but go with CDs when I'm actually interested in most of the album. I want higher quality, and I want to be able to go to other formats in the future if I ditch my iPod.

I'm not sure 256 or even 320kbps are necessary though. Your ears may vary, but from the controlled listening tests results i've seen, when you get to ~200kbps VBR with either AAC or MP3, most CD quality audio becomes indistinguishable to most users with decent equipment.
posted by Good Brain at 9:37 PM on March 31, 2005

Get the highest quality tracks that you can, if you are eventually going to use better equipment you definitely will hear the difference. Ever since I bought a pair of Shure e3c headphones for my iRiver I have deleted all 128 Kbps songs, they sound like utter crap and believe me I'm not an anal audiophile. Now I'm only listening I to 320 Kbps rips and I have also started messing around with the APE and FLAC formats because the guys at Rockbox are hacking firmware for the iRiver that will allow it to play those formats.

If space is not an issue, get the highest quality tracks that you can.
posted by sic at 11:13 AM on April 1, 2005