Uncompressed great even optical

[BTBuck1]

So last night I watched my first Blu-Ray with LPCM on my ps3. (A Knights Tale) I don't know why, but I always assumed that Uncompressed LPCM only benefited those with multichannel analog outs (like My samsung bdp1000& Tosh HD-A1) I also always thought that if you selected it using optical output that you'd get no sound, or that it would sound exactly like Dolby Digital. Well I selected it on Knights Tale and Immediately I had to cut the volume in half. Everything was louder and more dynamic sounding, even through OPTICAL!!! I was shocked!

I guess it's my own dumb fault for assuming all this time, but I heard that optical lacked the bandwidth and all that, so my question then is...what am I getting? It says 48khz, 4.5mbps 5.1 channel. It sounded awesome, and even my 6th channel was blazing out sound (neo6 was selected) which was probably why.

Anyone know how much of the 48khz, 4.5mbps i'm actually getting out of optical? It sounded nearly as good as my samsung outputting lpcm over analogs...if not AS good.