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Old October 1st 07, 05:18 AM posted to rec.audio.tech,rec.audio.car,rec.radio.shortwave,ba.broadcast
jhardis jhardis is offline
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First recorded activity by RadioBanter: Oct 2007
Posts: 3
Default HD RADIO is no worse than DAB or DRM radio

On Sep 30, 4:50 am, SFTV_troy wrote:
I don't know much about the Satellite services, but I see sirius uses
AAC (no plus). AAC is not much better than MP3


This whole thread is disturbing for the level of misinformation within
it. Let's take these two convenient examples.

1) Sirius satellite radio uses a codec called PAC. While PAC and AAC
are both "perceptual" codecs, and while they are both rooted in some
very early Bell Labs research and patents, the two are completely
different and nowhere near compatable with each other. (XM uses a
Coding Technologies implementation of HE-AAC, trade named aacPlus.)

2) AAC is a huge leap forward from MP3 -- that's the whole point of
it. The MPEG working group was unable to improve codec technology
while staying forwards and backward compatable with MP3. So, they
started over with a clean slate. AAC (no plus) is the compression
format that iTunes uses. (The iPod plays both AAC and MP3 files, but
AAC is the preferred format.) You are free to experiment on an iPod
comparing the same material encoded to the same compression ratio
using alternately MP3 and AAC.

- Jonathan