Newbie DVD Audio Question

[Toss]

Hi,

My first post!

First of all I have to say I know nothing about DVD audio.

I have a dvd player with an on-board Dolby Digital Decoder. At the minute my dvd player is only attached to my stereo, with two speakers.

I assume this setup is not making best use of DVD audio channels. Can someone recommend something I can do to make better use of the dolby digital audio and or DTS, on a small budget?

Any links to help me educate myself on dolby digital / dts audio would be appreciated.

[Mycophiles]

I'm in the same predicament.

I'm ripping avi's to svcd for viewing on my tv with adjoined surround sound system. My problem is that the audio doesn't come through as well as I would expect or think it could possible come through.

Do avi's converted to svcd use 2 channel stereo or surround sound? (using tempenc) If not how would I rip the audio using Nandub and then covert from 2 channel stereo to dolby digital surround sound.

(I don't mean to hi-jack the thread but I believe your topic is exactly the same as to what I'm trying to find out. )

8)

[ricky1756]

besides a dvd player with 5.1 sound you always need an amp with a 5.1 .
for the full effect of 5.1, you need 2 front speakers, 1 center speaker, 2 rear speakers and a sub woofer.

[ricky1756]

mycophiles, for just surround sound, its encoded in the 2 channel input, you need an amp that can decode it, and 2 front, 1 center, 2 rear. the two rear channels are mono, as opposed to 5.1 which has 5 discrete channels and a subwoofer channel

[Mycophiles]

Yes. That's exactly what I have. I have the dvd player plugged into the reciever w/ 5 sattalites and a sub.

If others are getting the 5.1 sound from an svcd then I'll check my reciever settings.

[Mycophiles]

Note to self: Always check dvd audio options.

*(brand new dvd players come defaulted to stereo )

[Mycophiles]

Wait wait. How did I not see it before.

What's this about the two rear speakers being mono while the others being 5.1 stereo? How do I do that.

My setup goes like this. TV-->RF MODULATOR --> Audio into cd/dvd on reciever and Video in the DVD Video out

Now:

The DVD --> Coaxial Digital plug into Reciever.

When I do a test signal -to the speakers- w/ my reciever it shows: Dolby Digital 2/0 (which I believe means it's not true Dolby) Though sound comes through all the speakers -when playing (true) dvd's. I have Diff surround sound settings on the Reciever (surround/audio 1/audio2 audio 3/ L. House/Jazz/Game. The dolby digital light pops up only when I have it set on audio 1=2=3.

So what's this about the surround sound being on mono?

____________________________

this is a guess but I'll take a shot in the dark. On the back of the sub there are two speaker plugs for right and left speakers (and also two input plugs for an amp {both too and from} ) The sub has an internal amp of 50 watts from what the manual says.

I've never understood what these plugs were for b/c the manual doesn't say anything about thier function but could these be the plugs for the surround?

(I prob. got this all backwards now. )

T

[Ste]

Wait, so do you have your sub hooked up with the L and R RCA jacks or are you using the speaker wire terminals?

Since your sub has an internal amp, you'd definitely would want to use that. If your receiver has a subwoofer pre-out (single black RCA jack) on the back of it, then you should connect it directly to the L jack (or L and R if you use an RCA splitter) on your sub....nothing else. If you are bypassing your speaker wires into your sub, then you have it hooked up in passive (not powered) mode. You should only do this if your receiver doesn't have that subwoofer pre-out I mentioned. I can get all technical about 'why' this way is better, but I wouldn't want to confuse you further. Just listen for yourself.
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Ok, now about the mono rear channel that ricky1756 was talking about. He was refering to Dolby Pro Logic decoding which takes a stereo signal (let's say from an SVCD) and virtually creates 2 additional channels: 1 center channel and 1 rear channel. This leaves you with a 4.0 signal. Even if you have 5 speakers, both rear speakers will have the same sound because there is only 1 rear channel produced from this type of decoding...hence "mono rear channel".

This type of decoding technology is quite old, but most new receivers come equipped with an updated version called Dolby Pro Logic II. This version takes a stereo input signal and leaves you with full surround sound: 2.0 -> 5.1
If your receiver has this mode, then you should definitely be using it. My receiver is on this mode 95% of the time. To check if you have this feature on your receiver just find the Dolby Digital logo on the front panel, and if it says "Pro Logic II" right under where it says "Digital" then you're good to go. Otherwise you're stuck with Pro Logic I which is still pretty decent.

[Mycophiles]

I have the sub hooked up into the sub pre-out. I am not using the speaker wire plugs on the back of the sub. I guess they are for a manufacturer's choice of selling the sub with a 2 speaker set or a 5 speaker set.

Anyway. Thanks for explaining the mono channels and what that means.

I'm curious, since you know what your talking about I'd also like to know what PCM and stream mean.

On the dvd player audio menu it says something like PCM/Stream , PCM only.

What do these mean?

Just to summerize. The DVD is hooked up to the tv by coaxial/rf-modulator(video). The DVD is hooked to reciever by the coaxial optical plug. The TV audio is hooked into the cd/DVD on the reciever.

This is the only way that these pieces of equipment work togeather. (basically b/c the TV only has the old style coax plug)

Everything seems to work but the surround sound when I'm playing DVD's. The audio doesn't seem to be in Dolby Surround.

I promise this is my last question. :P

This is the reciever. I found out it does not have prologic II.

http://www.epinions.com/597417_Sony_STR_DE475_Dolby_Digital_DTS_Receiver/display_~reviews

I guess that answers my question.

[Ste]

PCM stands for Pulse Code Modulation. It's basically a digital stereo signal, so it can only travel through an optical cable or digital coaxial cable. Since this is in an uncompressed format, it takes up a lot room on media. Typical audio CD's are encoded in this format.

Bitstream is exactly as it sounds. A series of binary numbers (0110100101110101 etc.) that gets fed into the reciever for decoding. This is what a Dolby Digital signal uses. It's a compressed digital signal, so you can fit more audio channels on the same space that PCM would take up. This is where you get your 5.1 from.

Put your DVD player on PCM/Stream since your receiver can decode Dolby Digital and DTS. The "PCM Only" setting is for devices that can't.
I'm not a big fan of Sony equipment, so I don't know what setting you're gonna have to put your receiver on...most equipment usually detects Dolby Digital automatically.

You also might want to hook up the TV's audio to like Video 1 or 2 or something else on the receiver to avoid human confusion, instead of CD/DVD. If your digital coaxial input on your reciever is also labeled CD/DVD, it might also cause confusion within the unit itself.

[duhmez]

In your DVD player settings, make sure to select dolby digital for output. Forget about any prologic nonsense as you said you have a dolby digital receiver via optical. Prologic is good if the source dvd is only 2 channel, or if its vcd/svcd etc.

Make sure the receiver is set to use the optical input too.

And dvd's typically (On all ones ive seen) have the 5.1 track as the first audio track by default too, so you shouldnt need to switch in the movie options

[Ste]

Many DVD players don't specifically list the words "Dolby Digital" in the audio settings. They might say "bitstream" or "SPDIF/RAW" depending on who made the player. The user manual should explain everything. Most manufacturers have PDF's of their product manuals on their websites in case you lose it.

But yea, duhmez puts everything into a nice summary.