[Mark A]

I read the archives, but assuming that one has the newest version of an iPod
(80 GB Video) and latest iTunes software (7.02), which one of these is the
best quality. All music is imported from CD's

MP3 - 320 kbps (stereo), VBR (highest quality setting), Sample rate (choice
of 44,100 or 48,000 kHz or Auto)

AAC - 256kbps (stereo), VBR, Sample rate (choice of 44,100 or 48,000 kHz or
Auto)

AAC - 320 kbps (stereo), No VBR, Sample rate (choice of 44,100 or 48,000
kHz, or Auto)

Note that with AAC, I cannot select 320 kbps with VBR using iTunes software.

[Serge Auckland]

Mark A wrote:
I read the archives, but assuming that one has the newest version of an iPod
(80 GB Video) and latest iTunes software (7.02), which one of these is the
best quality. All music is imported from CD's

MP3 - 320 kbps (stereo), VBR (highest quality setting), Sample rate (choice
of 44,100 or 48,000 kHz or Auto)

AAC - 256kbps (stereo), VBR, Sample rate (choice of 44,100 or 48,000 kHz or
Auto)

AAC - 320 kbps (stereo), No VBR, Sample rate (choice of 44,100 or 48,000
kHz, or Auto)

Note that with AAC, I cannot select 320 kbps with VBR using iTunes software.


I would suggest that as MP3 @ 320kbps and AAC at 256k (I understand that
AAC at 192k is considered indistinguishable) and above are both
indistinguishable from CD, that the question of which is better is
academic. If both are "perfect", then which "perfect" is better?

As 256k takes up less space than 320k, that's the one I would use. As to
sample rates, as the source is CD at 44.1, there can be no benefit at
using 48k, and if the sample rate conversion is not done very well, it
could well sound worse.

S.

[Richard Crowley]

"Serge Auckland" wrote ...
I would suggest that as MP3 @ 320kbps and AAC at 256k (I understand
that AAC at 192k is considered indistinguishable) and above are both
indistinguishable from CD, that the question of which is better is
academic. If both are "perfect", then which "perfect" is better?

Wow. I guess "perfect" doesn't mean what it used to.

[Serge Auckland]

Richard Crowley wrote:
"Serge Auckland" wrote ...
I would suggest that as MP3 @ 320kbps and AAC at 256k (I understand
that AAC at 192k is considered indistinguishable) and above are both
indistinguishable from CD, that the question of which is better is
academic. If both are "perfect", then which "perfect" is better?

Wow. I guess "perfect" doesn't mean what it used to.

I don't think the meaning has changed:- If an MP3 or AAC file is
indistinguishable from the original, then audibly, the copy is perfect.
There are no degrees of perfect, therefore it can't matter whether MP3
or AAC is used.

If you can show that 320kbps MP3 and 256kbps AAC are *not*
indistinguishable from the original, then the copy is *not* perfect, and
therefore there could be a choice to be made on quality grounds.

I am somewhat pedantic about the use of language - how many times has
one heard on TV or radio that something is "very unique"? Either
something is unique or it isn't, there are no degrees of uniqueness as
there are no degrees of perfection.

S.

[Richard Crowley]

"Serge Auckland" wrote ...
If you can show that 320kbps MP3 and 256kbps AAC are *not*
indistinguishable from the original, then the copy is *not* perfect,
and therefore there could be a choice to be made on quality grounds.

Perhaps indistiugishsable to some.

[Serge Auckland]

Richard Crowley wrote:
"Serge Auckland" wrote ...
If you can show that 320kbps MP3 and 256kbps AAC are *not*
indistinguishable from the original, then the copy is *not* perfect,
and therefore there could be a choice to be made on quality grounds.

Perhaps indistiugishsable to some.


Possibly, but the Fraunhofer Institute research I saw about 18 months
ago indicated as such.

S.

[Mark A]

"Serge Auckland" wrote in message
Possibly, but the Fraunhofer Institute research I saw about 18 months ago
indicated as such.

S.

My guess is that it depends somewhat on the type of music, and depends a lot
on the quality of the headphones. In my case you should assume that I might
be able to hear the difference and I want to know which one is best.

[Serge Auckland]

Mark A wrote:
"Serge Auckland" wrote in message
Possibly, but the Fraunhofer Institute research I saw about 18 months ago
indicated as such.

S.

My guess is that it depends somewhat on the type of music, and depends a lot
on the quality of the headphones. In my case you should assume that I might
be able to hear the difference and I want to know which one is best.



Subject to what I said earlier about the audibility of these codecs at
high bit rates, My choice would be for AAC, as it is a much more modern
codec, and therefore, I would assume would have fewer artifacts (audible
or not)than the older MP3. Whether VBR or not VBR, I would prefer to use
the higher rate and no VBR, for no better reason than additional
processing has to take place for VBR.

I can't give you an opinion based on audibility, as tests I've done
myself show *to my ears* that 320kbps MP3 is indistinguishable from the
CD original. (actually 256k is too) I use AKG K270 headphones and either
Meridian or Genelec active 'speakers. I listen to a wide variety of
music, jazz, classical, rock and blues, and haven't yet found a track
that caught out the MP3 codec.

S.

[Laurence Payne]

On Sun, 05 Nov 2006 10:30:03 +0000, Serge Auckland
wrote:


Subject to what I said earlier about the audibility of these codecs at
high bit rates, My choice would be for AAC, as it is a much more modern
codec, and therefore, I would assume would have fewer artifacts (audible
or not)than the older MP3.

Maybe. Or perhaps it merely boasts a higher compression ratio.

[Arny Krueger]

"Mark A" wrote in message

"Serge Auckland"
wrote in
message
Possibly, but the Fraunhofer Institute research I saw
about 18 months ago indicated as such.

S.

My guess is that it depends somewhat on the type of
music, and depends a lot on the quality of the
headphones. In my case you should assume that I might be
able to hear the difference and I want to know which one
is best.

I'm quite certain that Fraunhofer Institute knows how to pick headphones and
music that can expose the worst in any perceptual coder.

[Arny Krueger]

"Laurence Payne" lpayne1NOSPAM@dslDOTpipexDOTcom wrote in
message news
On Sun, 05 Nov 2006 10:30:03 +0000, Serge Auckland
wrote:


Subject to what I said earlier about the audibility of
these codecs at high bit rates, My choice would be for
AAC, as it is a much more modern codec, and therefore, I
would assume would have fewer artifacts (audible or
not)than the older MP3.

Maybe. Or perhaps it merely boasts a higher compression
ratio.

There is a relationship between the two. The coder that performs as well
with higher compression is likely (within bounds) to peform better with the
same compression.

This can be a bounded effect because it seems like a given coder strategy
performs well over only a limited range of compression ratios.

"Mark A" wrote in message
. ..
I read the archives, but assuming that one has the newest version of an
iPod (80 GB Video) and latest iTunes software (7.02), which one of these is
the best quality. All music is imported from CD's

MP3 - 320 kbps (stereo), VBR (highest quality setting), Sample rate
(choice of 44,100 or 48,000 kHz or Auto)

AAC - 256kbps (stereo), VBR, Sample rate (choice of 44,100 or 48,000 kHz
or Auto)

AAC - 320 kbps (stereo), No VBR, Sample rate (choice of 44,100 or 48,000
kHz, or Auto)

Note that with AAC, I cannot select 320 kbps with VBR using iTunes
software.

If you have nothing invested in either choice, I would recommend starting by
making a blind comparison between AAC at 256k and AAC at 128k. Can you tell
the difference using familiar recordings? If not (and I suspect that may be
the case) try betwween AAC at 128k and 64k, &c. I would use 44.1k all the
time.

How do you run the test? Here's how. Choose a difficult-to-encode CD
track and encode it using all the different schemes that are under
consideration, and also one to wav (as a control.) Now decode each one to
wav and burn them all to a CDR. What you now have is a CDR that can be
played on a high quality system consisting of the same original coded in the
various ways. I advise having somebody else make the CDR so that you don't
know ahead of time which track is which.

I've done this test more than once, and I'm always surprised at how much
music can be compressed before it even sounds different--much less bad.
And yes, I included subjects with lots better hearing than me.

Norm Strong

[Mark A]

wrote in message
...
If you have nothing invested in either choice, I would recommend starting
by making a blind comparison between AAC at 256k and AAC at 128k. Can you
tell the difference using familiar recordings? If not (and I suspect that
may be the case) try betwween AAC at 128k and 64k, &c. I would use 44.1k
all the time.

How do you run the test? Here's how. Choose a difficult-to-encode CD
track and encode it using all the different schemes that are under
consideration, and also one to wav (as a control.) Now decode each one to
wav and burn them all to a CDR. What you now have is a CDR that can be
played on a high quality system consisting of the same original coded in
the various ways. I advise having somebody else make the CDR so that you
don't know ahead of time which track is which.

I've done this test more than once, and I'm always surprised at how much
music can be compressed before it even sounds different--much less bad.
And yes, I included subjects with lots better hearing than me.

Norm Strong

I was given an 80 MB iPod as a gift. After loading all of my 200 CDs on the
iPod at AAC 256k with VBR, I have only used about 25GB. I have no real
incentive in trying to save any space by going below 256k (besides which, I
have finished load all my music)..