MP3 vs AAC? (1 Viewer)

[DavidBelis]

I rip most of my cds as 320kbps MP3s, but they tend to take up a fair bit of space. I'm trying to conserve because even though I've got nearly 20 gigs of space on my new iPod, I have a lot of music on my PC to upload to it.

How does the sound quality differ between the two formats and is it worth reripping my cds as lower bitrate AAC?

 

[Patrick_L]

Lame v3.96.1 + EAC @ --alt-preset extreme (VBR) will save you space and keep your quality.

 

[Angelo.M]

At lower bitrates, e.g. 128 kbps, AAC seems more transparent to me. At higher bitrates, e.g. 192 kbps and greater, it's a wash.

I used to encode everything in VBR mp3 format, using "alt preset standard." Now, I encode in AAC at 192 kbps. Average file size is very nearly the same. For portable use, I think you'd find AAC at 128 or 160 kbps to be quite good.

 

[Brian L]

Well...a great topic for debate to be sure, but I really don't find the 128K AAC stuff to sound good at all. I tend to download the freebies from iTunes every Tuesday, and find the SQ of those to be universally poor. Maybe with the Apple earbubs, but even with a good quality but inexpensive set of phones (Sen PX100)128K they sound bad to me.

I may be predisposed to not like lower bitrates because I rip everything at 320K AAC (wasteful I am sure, but I have ripped almost every CD I own that I want to rip, and I have still 18G to go on my 40g iPod).

In any event, that's the reason I have only bought 1 single tune (U2's Vertigo)....the SQ just isnt there at 128K AAC.

Of course, IMHO, AFAIK, YMMV.........

BGL

 

[Angelo.M]

I generally agree.

I don't use 128 kbps, but have downloaded a few things from the Apple store and they are of decent, but not spectacular, quality. No worse to my ears than mp3 at 128 kbps.

I'm very happy with AAC at 192 kbps, however. Brian, have you compared 320 and 192 kbps?

 

[Brian L]

No Angelo, I have not done a 192 to 320 comparison, and knowing that many users have posted that it is damn good is what led me to say that I know I am likely wasting space on my iPod.

I have had it since March, and have thus far 221 Albums and 1946 songs all at 320K AAC (actually, I think there is even a lossless Rip of Govt. Mules "Dose" on there), and as I said, I still have almost 18g to spare.

So, my thinking was, with that much space to play with, just go for the best it can be short of lossless of uncompressed wavs.

But I guess it would be interesting to rip some stuff at a variety of rates and codecs, and do some careful listening.

BGL

 

[Kevin M]

AAC at 128kbps is IMO comparable to WMA at the same bit rate, that is to say better than MP3, understandable since they both use a more efficient codec then the aging MP3.
However, as some have said, if you go up to at least 192kbps the differences between the formats becomes increasingly negligible. I personally use MP3 at nothing less than 192 if I want any sort of sound quality.

 

[Angelo.M]

I agree. At bitrates of 192 kbps and better, formats sound about equally transparent to me (mp3 and AAC, at least). Of course, some folks feel that the added info of 320 kbps adds an element to the final result that is difficult to define but, nonetheless, essential (welcome to Psychoacoustics 101, tip your waitresses...).

At any rate, I think that, in principle, a good variable bitrate implementation of AAC, with average bitrates in the 200-225 kbps range, would probably strike a terrific compromise between 192 and 320 kbps. I believe the Nero encoder can do this.

 

[MarkHastings]

And always remember that MP3's are actually MPEG1 technology (which has been around for YEARS!) whereas AAC's are MPEG4 (i.e. Brand new compression technology).

 

[DavidBelis]

After reading some of the comments here (and on Head-Fi), it seems like 192kbps AAC is the perfect balance between quality and small file sizes, for my purposes. So I think I'll go with that.

I've got a question, though. If most of my cds are ripped as 320k MP3's and I want 192kbps AAC files, should I rerip them all onto my PC or can I just convert the files directly with iTunes? Will it make a big difference?

 

[Angelo.M]

Re-rip. Converting from one lossy format to another isn't a good idea.

 

[ScottCHI]

um....................

 

[Brian L]

I have ripped some 320K AAC files to 192 MP3 in iTunes. FWIW, the end result was not as bad as I expected. I would say it was listenable, although I would expect it would not do well if I A/B'd it with the 320K AAC source files.

The reason I did it was because I discovered that one of my DVD players could also play MP3, and I just had to try it.

So for giggles and shits, I ripped the entire Zep catalog, which I already had at 320K AAC, to 192K MP3, and stuck it on a single CD. I just found it mildly interesting to have the entire Zep catalog on a single CD.

But as everyone else said, its probably not the greatest way to preserve and enjoy your tunes....but it can be done.

BGL

 

[PhilBoy]

If you have a DVD writer you can get over 600 tunes on a single DVD (mp3 100% VBR) and play them on a standalone DVD player through your HT...

Handy for partays.

It works with DVD-R on a Tosh SD3900.