Quote from the article at AnandTech.com:
“While little is known outside enthusiast high fidelity circles, some DVD-A media and sampling are already shipping. Mitsubishi’s newest line of DVD players uses the processor that supports DVD-A. As you may have guessed, DVD-A is simply higher fidelity audio written to DVD media instead of CD. However, DVD-A has a data rate of almost seven times that of an audio CD. This allows us to encode/playback more channels at higher frequencies and bitrates. DVD-A supports five-channel audio while CD uses only two.
Azalia, Intel’s 8-channel digital audio codec, raises the bar significantly over the aging AC’97 codec. Although Azalia (and other derivative codecs) apply more channels and higher stereo frequency, the most conspicuous feature is a data rate four times that of AC’97. Similar 8-channel audio solutions from VIA will also utilize similar bandwidth and bitrate specifications.
With the newer 8-channel audio codecs, we will be able to listen to multiple DVDs with 5.1 channel audio while operating VOIP/telephony/modem devices on the same digital signal processor (DSP), completely unhindered. Using AC’97 based solutions (including the nForce2 Soundstorm MCP), playing two DVD’s with stereo audio is not possible.”
Read the full article here