The Seventh Taylor
Newcomer
I don't see why not, if H264 at high bitrate takes up 3 SPEs (apparently, and that's the most processor intensive decoding it will have to do), then there's loads of free room for other tasks.
The heaviest A/V processing task it gets to do is converting DSD (the SACD audio format) to high-resolution PCM. This takes 5 SPEs according to Sony. Check out this article: http://pc.watch.impress.co.jp/docs/2006/1117/mobile356.htm
The main reason why SACDs sounds so much better than regular CDs on the proper equipment has more to do with production/mastering than the technical merits of the format.
The main reason lies not in the signal-to-noise ratio, not even in the increased dynamic range or the higher resolution, but in the far better accuracy in the time domain. With 'red book' CD audio (44.1 kHz PCM), unless eveything in the chain from mastering to playback equipment is excellent, the audio often "sticks to the speakers": you can hear it coming from the left speaker and right speaker but there's almost nothing in between. SACD uses 64 times the sampling frequency of CD and the result is a far better reproduction of the sound stage.
I can hear no difference switching between the CD and SACD layers on hybrid SACDs.
I have done many SACD demos and found that even people (like me) without 'golden ears' can quite easily appreciate the difference between stereo SACD and CD. I've even had a person deaf on one ear who noticed a clear difference.
When you switch to multichannel SACD the difference is overwhelming. This is where the real benefit for me lies.
For more info about SACD on PS3 have a look at this FAQ: http://www.ps3sacd.com/faq.html
There's also a general FAQ about SACD: http://www.ps3sacd.com/sacdfaq.html