My experiment: MP3 and AAC with Mozart's Serenade in G maj

Archived from groups: rec.audio.pro (More info?)

I just got an iPod and am wrestling with codecs. With rock and pop
it's pretty easy. After a lot of playing around there was no
discernable difference between OGG Level 6, MP3 @ ABR 160k, or AAC @
160k. This was listening through a laptop with 2 different sets of
fair headphones. So I'm going with Lame MP3, forced stereo, ABR 160
with a 128 to 192 range.

With classical, it isn't so easy. All sound pretty similar until the
big crescendos. Then it seems like the audio comes dangerously close
to clipping with MP3. When I checked what the dynamic range was for
each file here's what I noticed:

Original WAV: +/- 5.1dB
MP3 ABR 160k (128 to 192k range): +/- 8.6dB (using Cdex 1.51 and Lame
MP3)
MP3 ABR 128k (112 to 160k range): +/- 8.8dB (using Cdex 1.51 and Lame
MP3)
AAC 160k (non-VBR or ABR): +/- 5.1dB (using iTunes AAC)

Of course, the 128k was me just fooling around. But check out how
closely the dynamic range was matched between AAC and the original.
You can heard it clearly too, even through the iPod earbuds. In fact,
that was the impetus behind me checking into it. The MP3s just sounded
a little "blown" at certain points.

In closing, I have about 10gb of OGGs at Level 6 (about 200kps) but
the iPod doesn't handle them. So I'm re-converting all my CDs and
looking to straddle that fine line between audio degradation I can
live with and still have enough room to put more than 7 songs on the
iPod (10GB, it's small but cheap).

I think I'm going to end up mixing codecs. I don't want to end up in
this OGG situation again by going strictly with AAC. But I don't want
my classical music riddled with peaky dynamics and digital artifacts.

Hopefully this will prove helpful to those in similar situations. My
results are by no means definitive or scientific. But I've been at
this for 4 hours and this is what I've concluded for now.

If anyone has any comments or can see some gross flaws in my approach,
your comments are appreciated.

Being a geek is a lot of work,
Brian

Archived from groups: rec.audio.pro (More info?)

Backpacker <rh128592@yahoo.com> wrote:
> I just got an iPod and am wrestling with codecs. With rock and pop
> it's pretty easy. After a lot of playing around there was no
> discernable difference between OGG Level 6, MP3 @ ABR 160k, or AAC @
> 160k. This was listening through a laptop with 2 different sets of
> fair headphones. So I'm going with Lame MP3, forced stereo, ABR 160
> with a 128 to 192 range.

> With classical, it isn't so easy. All sound pretty similar until the
> big crescendos. Then it seems like the audio comes dangerously close
> to clipping with MP3. When I checked what the dynamic range was for
> each file here's what I noticed:

> Original WAV: +/- 5.1dB
> MP3 ABR 160k (128 to 192k range): +/- 8.6dB (using Cdex 1.51 and Lame
> MP3)
> MP3 ABR 128k (112 to 160k range): +/- 8.8dB (using Cdex 1.51 and Lame
> MP3)
> AAC 160k (non-VBR or ABR): +/- 5.1dB (using iTunes AAC)

> Of course, the 128k was me just fooling around. But check out how
> closely the dynamic range was matched between AAC and the original.
> You can heard it clearly too, even through the iPod earbuds. In fact,
> that was the impetus behind me checking into it. The MP3s just sounded
> a little "blown" at certain points.


Have you tried variable (not average) MP3 at higher bitrates than 160? I
use VBR of 128-320 kbps and can't tell classical copies from the originals.


settings, enconders etc are those recommended at www.hydrogenaudio.com for
using LAME with the EAC ripper.

--

-S.
"We started to see evidence of the professional groupie in the early 80's.
Alarmingly, these girls bore a striking resemblance to Motley Crue." --
David Lee Roth

Archived from groups: rec.audio.pro (More info?)

mrivers@d-and-d.com (Mike Rivers) wrote in news:znr1091149314k@trad:

>> Why limit LAME to a maximum of 192k instead of using a VBR preset

> File size, maybe?

Yeah, that's one possible reason. Another is if the playback device cant
play 320kbps MP3 data (many early devices couldn't).

Since I have never even seen an iPod, it's kinda hard to know wether the OP
had a good reason for limiting the MP3 bitrate to 192 or not...

/Jonas

Archived from groups: rec.audio.pro (More info?)

I went with ABR over VBR because for the same reason I drive a manual
transmission car: control. I know: the computer is far smarter than I
am and an automatic transmission is a brilliant piece of machinery.
It's the illusion of control. I liked the idea that the computer
would at least shoot for what I wanted. But I should probably
consider VBR.

I limited to 192k because #1: Anything over that seemed a bit much and
#2: I have a small iPod.

What I SHOULD do is just encode at 128k AAC and not worry about it.
I'm spending far too much time and effort thinking about something
that isn't all that important.

Good thoughts all. Thanks.
Brian

Steven Sullivan <ssully@panix.com> wrote in message news:<cecd7m$rt5$2@reader1.panix.com>...
> Backpacker <rh128592@yahoo.com> wrote:
> > I just got an iPod and am wrestling with codecs. With rock and pop
> > it's pretty easy. After a lot of playing around there was no
> > discernable difference between OGG Level 6, MP3 @ ABR 160k, or AAC @
> > 160k. This was listening through a laptop with 2 different sets of
> > fair headphones. So I'm going with Lame MP3, forced stereo, ABR 160
> > with a 128 to 192 range.
>
> > With classical, it isn't so easy. All sound pretty similar until the
> > big crescendos. Then it seems like the audio comes dangerously close
> > to clipping with MP3. When I checked what the dynamic range was for
> > each file here's what I noticed:
>
> > Original WAV: +/- 5.1dB
> > MP3 ABR 160k (128 to 192k range): +/- 8.6dB (using Cdex 1.51 and Lame
> > MP3)
> > MP3 ABR 128k (112 to 160k range): +/- 8.8dB (using Cdex 1.51 and Lame
> > MP3)
> > AAC 160k (non-VBR or ABR): +/- 5.1dB (using iTunes AAC)
>
> > Of course, the 128k was me just fooling around. But check out how
> > closely the dynamic range was matched between AAC and the original.
> > You can heard it clearly too, even through the iPod earbuds. In fact,
> > that was the impetus behind me checking into it. The MP3s just sounded
> > a little "blown" at certain points.
>
>
> Have you tried variable (not average) MP3 at higher bitrates than 160? I
> use VBR of 128-320 kbps and can't tell classical copies from the originals.
>
>
> settings, enconders etc are those recommended at www.hydrogenaudio.com for
> using LAME with the EAC ripper.