Player decoding or Receiver decoding

[admin_exported]

I find it better for the receiver to do it, the soundtrack has much better timing.

I wonder if thats the same for other makes of AV amps or just Onkyo's?

 

[Anonymous]

Bitstream v LPCM

There's no reason why bitstream should sound the same as LPCM. The digital audio replay architecture is different, and that means the sound may be different.

A digital audio signal has two elements - a data stream and a timing stream. Both of these end up at the DAC to create the analogue audio signal, and both need robustness and fidelity.

These streams are quite distinct, and take different critical paths:
The data stream starts at the disc, and ends up at the DAC.
The timing stream starts at the master clock in the PS3, and also ends up at the DAC.

The bitstream decoding process ONLY affects the data stream, and the DAC is receiving the right data, whichever decoding architecture is used.

However, this architecture MAY affect the path of the timing stream . With LPCM, the clock is in the transport, and the path takes the HDMI connection to the receiver and to the DACs. This is a tortuous path, and is full of degradation - like toslink but worse.
With bitstream, there's no clock associated with the data because its compressed, and the clock is regenerated IN the amplifier, just as it is with DD and DTS. This places the clock right next to the DAC, with robust and direct connection, you can't better that. This doesn't eliminate interference, noise and jitter, but it's a very big help. The same information is put out but one is processed by the player and the other by the AV amp. It's clear on listening to me that the Onkyo 875 does a better job of it.

So with bitstream there is an opportunity to minimise jitter, though this is ONLY achieved if the amplifier doesn't generate its audio clock from the players video clock, in the same way it does with LPCM. I think Onkyo don't, but other amplifiers might (I don't know). What I do find is the timing and 3 dimensionality is head and shoulders better with what is played out from the speakers. Now with the PS3 being such a big seller for Blue Ray I think this is very important.

 

[professorhat]

Blimey Trevor, this has really captured your attention at the moment hasn't it?!

ÿ

 

[Anonymous]

Trev

Doesn't the PS3 only output PCM anyway..?

 

[Andrew Everard]

Eddie Pound:Doesn't the PS3 only output PCM anyway..?

Well yes, at least from HD soundtracks. But sssshhh - you're interrupting Trev's internal monologue...