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ezra2323
Last time Roberto conducted one of his listening tests, Apple's MP3 encoder scored miserably - comparable to some very out dated MP3 encoders!

I read that the MP3 encoder was significantly upgraded with the release of iTunes 4.5. While I have no illusions of it producing files at 192 or 224 or even 256 comparable to LAME alt preset standard, has anyone tested it to see if there is a significant improvement in quality?
Gabriel
QUOTE
I read that the MP3 encoder was significantly upgraded with the release of iTunes 4.5.

Where did you get that info?
Busemann
I think it is the AAC encoder you are thinking about, it got several enhancements with the latest update.

Which begs the question; why not use that for the next listening test blink.gif
xmixahlx
...*sigh*

try the search button, or follow the thread to an obvious conclusion


later
ezra2323
QUOTE
Where did you get that info?


I cannot recall - it was either here, on Apple's web site, or on Head Fidelity. I cannot recall the validity of the source which is why I was asking if it was true.
Mike Giacomelli
QUOTE(Busemann @ May 14 2004, 01:06 AM)
I think it is the AAC encoder you are thinking about, it got several enhancements with the latest update.

Which begs the question; why not use that for the next listening test  blink.gif

Because quality is less then the older version evidently.
Busemann
QUOTE(Mike Giacomelli @ May 14 2004, 03:49 PM)
Because quality is less then the older version evidently.

Well, thats not what people will say if 4.2 looses...
ezra2323
Correct me if I'm wrong, but isn't the fact that iTunes now offers MP3 VBR encoding new? I cannot honestly say I even bothered with iTunes MP3 encoder prior to 4.5 so I may be wrong, but I thought I remember seeing CBR options only before.
guruboolez
IIRC, Roberto used itunes's VBR mode for the MP3 128 kbps test (VBR 112 kbps). So VBR can't be something new for iTunes 4.5
ezra2323
QUOTE
Roberto used itunes's VBR mode for the MP3 128 kbps test (VBR 112 kbps).


You are right.
ff123
QUOTE(Busemann @ May 14 2004, 04:00 PM)
QUOTE(Mike Giacomelli @ May 14 2004, 03:49 PM)
Because quality is less then the older version evidently.

Well, thats not what people will say if 4.2 looses...

What would "people say" if 4.5 loses: "You didn't test the version with known good quality. You know, the one which won the AAC test!"

The limited listening evidence so far supports the idea that 4.5 regressed in quality compared to 4.2.

ff123
Busemann
QUOTE
The limited listening evidence so far supports the idea that 4.5 regressed in quality compared to 4.2.

ff123


Actually, thats not true.. The changes the two guys that tested the new codec here got upset about was that high frequency sounds were more apparent. Its closer to the original now, although the slightly more "muffled" sound of 4.2 are probably more ear friendly..

At 128kbps the QT 6.5.1 encoder is better. (check the apple boards for more discussion)
rjamorim
QUOTE(Busemann @ May 19 2004, 04:56 PM)
The changes the two guys that tested the new codec here got upset about was that high frequency sounds were more apparent. Its closer to the original now

Wrong. They complained about ringing. smile.gif

I'm sure the listeners wouldn't be unpleased if the high frequencies were there - in a faitful representation of the original.

After all, since when "high frequency sounds more apparent" make listeners upset?

QUOTE
(check the apple boards for more discussion)


Of course. Just look at the graphs. Frequencies all the way up to 19kHz. That must mean quality rocks! biggrin.gif
32bitwonder
Dispite what's been said about previous versions of the iTunes MP3 encoder, I decided to do my own informal listening tests with 4.5. I ended up pleasantly surprised and I'm now kicking myself for not having tried it sooner as I've found the MP3 encoder in iTunes 4.5 to be quite good. The settings I'm using are:

Bit Rate: 192 kbps
VBR: yes
Quality: Highest
Sample Rate: Auto
Channels: Auto
Stereo Mode: Joint Stereo
Smart Encoding Adjustments: yes <--Does anyone know what this actually is?
Filter Frequencies Below 10 Hz: no

I'm sure it'll be argued that any MP3 encoded at settings similar to this will do well, and that's true. I'm simply surprised how detailed iTunes encoded mp3s sound to me, I wasn't expecting this at all. I for one would welcome a more formal comparison.
dev0
While this is certainly an interesting subject, TOS#8 has to be respected.
Informal listening tests are worthless. Come back with ABC/HR results.
magic75
QUOTE(32bitwonder @ Jun 1 2004, 08:36 AM)
I for one would welcome a more formal comparison.

How about Robertos listening test of MP3 codecs @ 128 kbps ? iTunes was clearly the worst.

192 kbps is a very high bitrate and I am not surprised that you find it to sound good to you. You should try it at lower bitrates and compare it blindly to Lame for instance. I am pretty sure you won't find it as good then.
Mike Giacomelli
Try fatboy.wav. that used to break iTunes MP3 horribly, even at 320kbps.
dev0
[TOS#8 violation moved to the Recycle Bin.]
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