QUOTE (adlai @ Jun 26 2009, 17:20)

I just encoded an audiobook from 16 cds into a single .m4b file. I used nero audio 0.15...and it's 225 mb.
How low is it advisable to go for audiobooks? I'm thinking of experimenting with like 0.05
depends on your preferences really. i'd suggest you go ahead and experiment alouth it would be advisable to just pick a small section to experiment with rather than re-encoding the whole thing.