[sdiy] Digital noise sources

[Tom Wiltshire]

Sorry to go back to this again, but I wonder if someone could clear  
something up for me. There's something I don't understand:

What's the difference between outputting a random stream of bits at  
high frequency (1-bit digital noise) and outputting a  series of  
random bytes to a DAC (8-bit digital noise)?

Are they equivalent? Is one better than the other?

If someone who understands digital better than I could explain this,  
I'd be very grateful.

Thanks,
Tom


PS: Just for grins, I saw this on ebay:
http://cgi.ebay.com/ws/eBayISAPI.dll? 
ViewItem&item=290217442449&ssPageName=ADME:B:FSEL:US:1123

I know how much you'll all be wanting to snap one up!