New PB digital audio specs question.

I just looked at the specifications posted on the developer note for the new powerbooks. The digital audio in/out is very welcome. As I read through it, I found that the PB is listed as providing digital audio output via SPDIF AND AC3 formats. The question is, does anyone know if that AC3 output means its passing multichannel AC3 to be decoded outside? or is it a stereo AC3? Can anyone check? thanks... btw, the specs look good for digital in/out.

Thanks for your post, Machive 6.1. I had in fact read that article... in only states the following about AC3:
During playback of a 1KHz, full-scale sine wave (S/PDIF output format, 44.1KHz output sample rate, 24-bit sample depth, unless otherwise specified) the digital audio output has the following nominal specifications:
Jack Type: 3.5mm Analog/Optical Combo Jack
Output Data Formats: S/PDIF (IEC60958-3), AC3
Output Sample Rates: 32KHz, 44.1KHz, 48KHz, 64KHz, 88.2KHz, 96KHz
Bits per Sample: 16 or 24 (S/PDIF),16 (AC3)
Frequency Response: 20Hz – 20KHz, +/-0dB
Signal-to-Noise Ratio (SNR): >130dB
Total Harmonic Distortion + Noise (THD+N): <-130dB (0.00003%)
Channel Separation: >130dB
It is not clear whether that is multichannel or stereo AC3 output...
Anyone has tried it?

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