iTunes Ripping Speed Feedback

William Hofius wjh at mac.com
Tue May 27 07:08:14 PDT 2003


Kunga,

I have both a Dual 450 MHZ PowerMac G4 and an 800 MHz TiBook. The speed limitation you refer to only affects ACC conversions and not MP3. When I run iTunes 4 on my Dual PowerMac, the details of my Import settings for the MP3 Encoder are:

80 kbps (mono)/160 kbps (stereo), VBR (Highest Quality), joint stereo, optimized for Velocity Engine, dual processors.

Switching over to the ACC Encoder, the details for my Import settings chnage to:

80 kbps (mono)/160 kbps (stereo), optimized for Velocity Engine.

When I run iTunes 4 on my TiBook, the details of my Import settings for the MP3 Encoder are identical minus the dual processors line. For the ACC Encoder, the details are identical for both machines.

Quite simply, the iTunes MP3 Encoder makes use of dual processors whereas the iTunes ACC Encoder cannot. Since the ACC Encoder is a function of QuickTime and not iTunes, the fault would lay with QuickTime and not iTunes.

FWIW, uisng the internal drives on my two Macs, I get about the same rip-rate. MP3s typically rip anywhere from 12x to 16x. As you can see, dual processors do make an important difference when using the MP3 encoder.

The real question would be, why hasn't Apple designed the ACC encoder to be "optimized" for dual processors. That question should probably be expanded to QuickTime itself, or all of Apple's digital media applications that need to encode data.





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