PCM sound Question

[jee]

Sorry for what is likely a very repetitive question.

I have the Sony STR-K900 Reciever, which has 2 optical inputs, a coaxial and 2 HDMI. The HDMI Inputs are video only (acts as a switch that forces a maximum of 1080i), thus I dont use the hdmi on the receiver.

I have my PS3 hooked up too the reciever with optical cable. My question is, does PCM 5.1 work with any or most 5.1 recievers? Or do you need the latest and greatest for it?

When I enable PCM 5.1 as opposed to the regular DD 5.1 or DTS 5.1, the sound seems alot louder. But im curious, is it actually decoding the 5 channels properly or should I stick to the old DD and DTS soundtracks?

Thanks in advance.