when using a fibre optic cable? i have the 360 hd-dvd add on, and have a very hard time discerning any difference between the DD and the DolbyTrue HD formats (these seem to be the only 2 options available on any of the 5 titles i own).

and if i had the option would DTS be better? i know its my prefered format when watching SD DVD's and given the choice of DTS or Dolby 5.1.

TOSLINK (and SPDIF) cannot carry TrueHD at all, due to insufficient bitrate-capacity.
This was copied from here:
[Link: en.wikipedia.org]

DTS is preferred on standard DVD's. But from what I have read there is not a lot of difference between DD+ and DTS on HD-DVD's. TrueHD is better than either one though.

good read there bookaroni, thanks for the link. pardon my ignorance but can i assume TOSLINK is a fibre optic cable?

from what i gather then, you cant actually take advantage of Dolby true HD without an HDMI 1.3 connection?

that being the case, what format am i actually hearing when i put it into the True HD format while watching an HD-DVD via my 360 and a fibre optic cable?

Not completely sure what the sound output is on the 360 thru the toslink. But I will guess it is DD+.
I listen to TrueHD through analog outs on my Toshiba XA-2 as I have no HDMI connection either. But alas, your 360 does not have analog out.

And yes, Toslink is your fibre optic (optical) cable.

True HD (uncompressed) is absolutely awesome. Do you have the Elite version? I'm thinking you might as it is the only one with optical out. HDMI out too, but only the 1.2 version.

the 360 elite? yes i do. and yes i understand it is only 1.2 hdmi. FYI the regular 360, aswell as the old xbox for that matter, have optical outputs.

thanks again for the info bookaroni, that would explain why there is no discernable difference when i switch between formats!

I bought a Toshiba HD-A2 yesterday only to discover that the best audio through optical I could get was prologic (same signal to each rear speaker). My Sony receiver doesn't do DTS and has no HDMI inputs. So today I ordered sony's STR-DG1000 at a fair price from etronics.com. The higher resolution of HD-DVDs isn't enough to justify their higher cost without at least 5.1 DD audio.

That makes no sense. Thru optical it should do 5.1. If you hit info on your Toshiba remote it will tell you what is going on. At the top is the Video codec used. Next is audio- English Dolby D.
What does yours say?

My manual explains that if the receiver doesn't do DTS, then I have to set the A2 to send PCM down the SPDIF cable to get any sound at all. My receiver reports Dolby Prologic. I'll check on what INFO reports from the A2's end next time I use it. Trust me though, as I spent nearly a whole day trying to get the blue light on my receiver to come on via the optical hookup from the HD-A2. The HD-A2 only sends 5.1 if it's set to raw (bitstream) data thought the spdif. My receiver doesn't see anything (no sound) in this mode.

Digital out SPDIF should be set to Bitstream, not PCM.
This part-
"My receiver doesn't see anything (no sound) in this mode."
You mean the LCD screen shows nothing on your receiver?
And you have no sound at all?
I'm going to hook up my optical cable and get back to you.
In the meantime is the Sony you have hooked up now the STR-DG1000. Or a different Sony.
Your A-2 does DTS, doesn't it?

Using a standard DVD-
Using my optical cable my receiver says Pro Logic Normal. But in the lower left corner it says-
Digital Source AC-3

Using an HD-DVD-
I can play DTS sound. But I have a DTS receiver. And my hookup will not play DD+ using the optical cable in the bitstream mode.
To use the optical for DD+ I have to change the DVD player to PCM. Then I need to toggle the input mode on my receiver. Here are my toggles-
Analog
DTS
Auto
Auto will automatically bring up PCM as a source.

Right. When set that way the old receiver that does not do DTS does not know how to analize a bitstream DTS signal. So I HAVE to set the A2 to PCM and when set that way my receiver DOES emit sound and the LCD reports Prologic and show icons of a center, left, right, sub, and one rear speaker.


Right


An old Sony STR-DE825. I've ordered the STR-DG1000 but don't have it yet.


Yes.

Set the DVD player to bitstream and toggle the input on your receiver to auto. That should give you DD+.

hmmm. i find this all quite interesting. the xbox has very limited functions as far as audio adjustments etc, however my Pioneer SD DVD upscaler has many. so if using optical i should have it set to bitstream?

i recently bought a bunch of rca's so i could listen to sacd's and dvd-audio's (now good luck finding one locally that i would want to listen too!), so i now have the multi channel out option for my dvd player and reciever. do i have to set the dvd to pcm to take full advantage of the multi channel analog out?

i have only compared by switching inputs back and forth on my reviever (standard to multi channel). i didnt find any improvment in sound using multi channel, in fact i prefered the standard sound via the toslink, i think due to the fact my reciever is not doing ANY processing when accepting the multi channel input....?

"do i have to set the dvd to pcm to take full advantage of the multi channel analog out?"

Well, I'm not sure. PCM audio is supported by the DVD standard but rarely used.
PCM is a digital form of an analog signal. Straight PCM uses a high bitrate. So it is usually compressed. If compressed too much it will be lossy for sure. I have no idea what happens to a PCM signal using analog out.
The main reason to use PCM is because your receiver has no decoding capability. And that would be a pretty old receiver as most receivers have some sort of decoding capability. Such as Dolby Digital or DTS. So if your receiver is Pro Logic, then yes use PCM.

you can see my reciever in my sig, bitstream it is for me then! thanks alot for the info bookaroni.