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Krafty
Mar 27, 2008, 08:46 AM
Yesterday on my shuttle bus I overheard someone talking about AAC sounding better than MP3, and that MP3 only sounded good at 192kbps+, is this true? I like my music at its best, so should I covert all 52GB of my music to AAC?



~Shard~
Mar 27, 2008, 08:49 AM
In general AAC is higher quality at the same bit rate, so you can use a smaller file to achieve the same quality as MP3. So, for a nice portable format I'd definitely choose AAC - otherwise, if you have the disk space, go Apple Lossless. :cool:

Sky Blue
Mar 27, 2008, 08:50 AM
I've you reconvert your MP3s to AAC, you're going to end up with worse quality.
Personally, I prefer AAC to MP3. If you're converting from a lossless format you can try it.

kuebby
Mar 27, 2008, 09:37 AM
Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU like Mac OS X; en) AppleWebKit/420.1 (KHTML, like Gecko) Version/3.0 Mobile/4A102 Safari/419.3)

^seconded. Reencoding is not worth it. I use mp3 and I'm perfectly happy with it, it's the widest used standard so I'll always be able to listen to my music.

munson
Mar 27, 2008, 09:43 AM
Also, I'm pretty sure .aac files are drm encoded, so you cannot use someone else's unless their computer is authorized, but I could be wrong. But, as far as Apple Lossless goes, there's no point unless you're using nice audio equipment (spekaers/eadphones) because most can't even play music back with the quality that Apple Lossless encodes it with, ha ha...

~Shard~
Mar 27, 2008, 09:44 AM
Ah, I didn't catch that part. Yes, if you're debating re-encoding your MP3 collection to AAC, don't bother - you cannot gain back what you have already lost through initial compression. If you are considering re-encoding your original library of CDs however, then it would definitely be worth it.

Sky Blue
Mar 27, 2008, 09:46 AM
Also, I'm pretty sure .aac files are drm encoded, so you cannot use someone else's unless their computer is authorized, but I could be wrong.

Yes, you are. Most music from the iTunes store has DRM, but any AAC file you encode yourself does not.

AliensAreFuzzy
Mar 27, 2008, 09:52 AM
Also, I'm pretty sure .aac files are drm encoded, so you cannot use someone else's unless their computer is authorized, but I could be wrong. But, as far as Apple Lossless goes, there's no point unless you're using nice audio equipment (spekaers/eadphones) because most can't even play music back with the quality that Apple Lossless encodes it with, ha ha...

Only AAC files downloaded from iTunes have DRM protection. If you import them yourself from CDs, there's no DRM.

PlaceofDis
Mar 27, 2008, 09:52 AM
aac format has nothing to do with drm unless its purchased content from iTunes.

it does offer higher quality sound at a lower bit rate than MP3, but its not worthwhile to re-encode from an MP3 file as you'll actually lose quality. if you wanted to re-import from disc you would be able to save space though. 128kbps aac is about equal to 192kbps MP3.

Eidorian
Mar 27, 2008, 09:53 AM
I go with LAME MP3 just for the sake of compatibility. I think that AAC is just plain better though. ;)

cmcbridejr
Mar 27, 2008, 01:03 PM
AAC is a format developed by Dolby and nearly every DVD movie you watch has the audio tracks burned as AAC.

If AAC is good enough for Dolby and the audio engineers that work for Hollywood film studios, then it is certainly good enough for me.

Also, I have a "trained" ear and can usually tell the difference between 128 AAC vs MP3.

However, when you start to go above 256, it gets harder to tell the difference.

I import all CDs at 320 AAC and this sounds like CD quality to me.

killmoms
Mar 27, 2008, 01:08 PM
AAC is a format developed by Dolby and nearly every DVD movie you watch has the audio tracks burned as AAC.

No, they don't. DVDs use Dolby's Dolby Digital AC-3 format, or DTS. Neither of these are AAC.

Krafty
Mar 27, 2008, 01:27 PM
Very helpful responses indeed.

I upgraded to 250GB not too long ago, so disk space really isnt an issue. So I suppose I'll start importing CD's at AAC instead.

Thanks for the info.

~Shard~
Mar 27, 2008, 01:28 PM
AAC is a format developed by Dolby

For the record, AAC was developed by the MPEG group that includes Dolby (among many others). :cool:

killmoms
Mar 27, 2008, 01:28 PM
Keep in mind, an increase in bitrate will net a larger quality improvement. I'd say if you have plenty of disk space to work with, go up to 192 or 256kbit AAC (with VBR turned on).

supercooled
Mar 27, 2008, 11:35 PM
I would caution against AAC as you would eliminating people without iPods. How many portable players out there that can play AAC as well as the plethora of formats out there? I still have a few PC centric devices around which need MP3 for compatibility reasons so I encode in 192kbps which is pretty close to CD quality for me. And 90% of stuff out there is MP3. Yes, I download! I cannot lie!

gnasher729
Mar 28, 2008, 04:45 AM
I would caution against AAC as you would eliminating people without iPods. How many portable players out there that can play AAC as well as the plethora of formats out there? I still have a few PC centric devices around which need MP3 for compatibility reasons so I encode in 192kbps which is pretty close to CD quality for me. And 90% of stuff out there is MP3. Yes, I download! I cannot lie!

Every new device comes out with AAC decoding. The only reason why older players didn't was because they were afraid of Microsoft - you couldn't get the "Microsoft Play for Shure" sticker (spelling as intended) and support AAC as well. Then Microsoft ****ed all its customers when it released the Zune that supports AAC and does _not_ support Microsoft's own "Play for Sure" thing, so this has been changing.

em500
Mar 28, 2008, 05:59 AM
There's a lot of half-truths and misconceptions regarding audio encoding floating around, that could use a good clearing up. I'll just try to summarize the main points.

- MP3 is by far the most popular music compression format with the widest compatibility. It's not really a Free or Open standard (like Ogg Vorbis is), as lots of organizations claim ownership and patents on parts of it, but in practice nobody gives a damn. It's non-proprietary in the sense that everybody can implement it as long as they pay the fees and many implementations are available. If you get a player (either hardware or software) from a brand name manufacturer, they (and by extension, you) already paid the license fees.

- Like most formats, the MP3 decoder is completely fixed in the standard, but the encoder is not, and different ones produce quite different quality. The consensus is that the Lame encoder produces the best output. A lot of older encodings and from lesser encoders aren't very good, which lead some to believe that the MP3 standard just isn't very good. The MP3 encoder in iTunes isn't particularly good, at least in older listening tests. I'm not aware of the MP3 encoder quality in recent iTunes, but I doubt they spent much more effort on it.

- In the majority of cases, Lame MP3 is extremely hard to impossible to distinguish from the CD source for most people with the standard presets, which produce variable bitrate files of about 165 - 245 kbps.

- AAC is a more modern codec that is theoretically better than MP3. The open/proprietaryness is about the same as MP3: lots of organizations claim varying parts of ownership, and everybody can implement it for a fee. More and more big name companies like Sony and Nokia are supporting it, especially in newer devices, but it's still not as widespread as MP3. Basically, everything that plays AAC can also play MP3, but the reverse is not true. Apple has chosen AAC as its default format, but many of the files you buy from their stores have additional encryption applied, called Fairplay. Once decrypted, they're standard AAC, but (officially) only Apple players have the decryption keys.

- Like MP3, the decoder is fixed, but there are different encoders, which compress with different quality. Apple's AAC encoder in iTunes is amongst the best. Nero has an AAC encoder that's roughly the same quality, but it's only available for Windows.

- Although AAC (and other modern encoders, like WMAPro and Ogg Vorbis) are theoretically better than MP3, most of the advantage are for lower bitrates. 64 or 96 kbps AACs sounds much better than same size MP3. Because most test are meant to show differences rather than similarities, and thus are conducted at lower bitrates where MP3 lose badly, some people believe that MP3 is just much worse than AAC. But at 128kbps, the difference is already pretty small, with maybe around 10% advantage for AAC (meaning that you probably need a 10% bigger file in MP3 to get the same quality as in AAC). At around 160kbps and over, the difference is negligible, which is to be expected, as it's also extremely hard to tell the difference between the 160kbps+ MP3/AAC and the source CD.

- Many people will claim to easily hear differences between [format of choice] and [format they don't like], but few can do it in a fair blind test.

- If you're paranoid (or expect the future may still bring new breakthrough compressions), you should probably use a lossless compression. The relevant ones are Apple Lossless, which play directly on iPods, and FLAC, which is most popular outside of Apple. Since all the information from the source is retained in all lossless formats, and compression ratios don't differ very much, the choice is mainly down to convenience, playback support, and metadata support (titles, album art, etc).

- You can always convert from one lossless format to another without loss of sound quality, but metadata may be lost. Converting from any lossy standard like MP3 or AAC to another will always result in degraded sound quality.

cmcbridejr
Mar 28, 2008, 08:23 AM
No, they don't. DVDs use Dolby's Dolby Digital AC-3 format, or DTS. Neither of these are AAC.

Sorry for the misinformation. I was wrong.

However, there are articles stating that AAC is certainly better than AC-3 or MP3.

Check out what Wikipedia says:

http://en.wikipedia.org/wiki/Advanced_Audio_Coding

If you are one of those people that thinks Wikipedia is not a "reliable" source, then scroll to the bottom of the page for references.