Uber Home Theatre, Doom3, SPIDF Out, and lack of 5.1 :-/

T

Techguy

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We've got a huge DLP projector, and a really nice 1800W 5.1 harmon/kardon speaker and amp setup, with a new pre-processor. I took my PC down to the home theatre, and hooked it up to the DLP Projector via a VGA cable. I borrowed the fiber cable from our XBOX and plugged that into my SPIDF out on my motherboard (ABIT IT7 Max2 v2). I figured hell, what can beat 1800W of digital surround sound for doom3....

For some reason it seems that my SPIDF out is only outputting a stereo signal. The audio works and all, but I'm only getting a L and R channel when I do a speaker test. I know 5.1 via fiber isn't an issue with our home theatre, our XBOX and DVD player both do it just fine.

Other than the fact that I had to play it in stereo and used the pre-processor to make it more surround sound feeling last night, doom3 looks great on the projector. I'll have to post pics tonight so you can see how awesome the setup really is :->

So my question is this, how (or can I?) do I get 5.1 sound via SPIDF out?

Thanks for any ideas on how to do the 5.1.
 
Well, I'm new to this whole HTPC deal so I might be wrong, but here is what I think is your problem. Even though you have the TosLink optical output on your motherboard, it is not encoding to DD5.1 surround. I'm willing to bet that if you were to play a DVD, the 5.1 would work just fine. The output on your motherboard is passing through the DD5.1 info from the DVD, but it is not encoding the audio from Doom3 to DD5.1. That is why the "SoundStorm" on the NF2 mobos is great for HTPCs. It will encode everything to DD5.1 in hardware so as not to use any CPU resources. I believe that there is software out there that will encode everything to DD5.1, but it will also use some of your resources to do so.

Correct me if I am wrong.
 
I would have to agree with the above poster about the problem. Unfortunatley, I only use analog for surround sound now from my computer.

BTW which DLP projector do you have? We're moving into a new house, and one part of the basement is perfect for putting in a home threatre. I was looking at the Infofocus entry level one for like $1800....that looks appealing. I've been reading up on home theatres like crazy, but some user experience is nice too. So which one do you use, and any reccomendations, tips?
 
I'm fine with killing a few CPU cycles to encode the sound to Dolby Digital get the 5.1.
Anyone know an app that will do this?

Thanks!

computerpro3, I'll get you the DLP specs when I go home tonight. My dad got the DLP while I was away at college, so I just use it, I've not really looked into it's specs. I'll also post a few pics then too.
 
Techguy said:
I'm fine with killing a few CPU cycles to encode the sound to Dolby Digital get the 5.1.
Anyone know an app that will do this?

Thanks!

computerpro3, I'll get you the DLP specs when I go home tonight. My dad got the DLP while I was away at college, so I just use it, I've not really looked into it's specs. I'll also post a few pics then too.
Click to expand...

There is no software that can do this in real-time as far as I know. Your only option would be to completely change platforms over to an NForce 2 setup, or just use the 5.1 audio outputs of your motherboard and run them to your receiver.
 
I have found that "AC3Filter" will encode WMV_HD to DD5.1. I don't know if it will do games or not. There has to be a solution out there somewhere.
 
So your using the output from your MB right? Have you setup your Sound Control Panel for Digital out? How about playing a DVD, can you get 5.1 when doing that?
Is this the board?
 
It's sounding like it's not passing the digital signal along but if it plays the DVD in 5.1 well know.
 
The way that I understand it is this...

A DVD is encoded with Dolby Digital 5.1 that can be understood by a Dolby Digital Receiver. This DD5.1 signal is passed through the SPDIF output of the mobo to the receiver and then goes out to the correct speakers. Likewise with DTS.

Games and stuff, although they are in 5.1 surround, are not encoded with Dolby Digital 5.1, so when it gets passed through to the SPDIF output to the receiver, the receiver can not decode it because it doesn't support anything but Dolby Digital or DTS.

The goal is to have either the soundcard (ie SoundStorm) encode it to Dolby Digital 5.1 in real time, or to have some sort of software encode it to DD5.1 in real time. Only then will your receiver be able to decode it.

Again, I might be wrong, but that is the way that I understand it. Not all 5.1 soundcards are created equal.
 
That sounds about right FlipperBizkut but I'm not sure if D3 outputs a 5.1 signal which is why I'm waiting for him to do the DVD test.
 
I fired up our Video Essentials DVD, and set PowerDVD's speaker setting to SPIDF and then I had a 5.1 signal. I can even enjoy DTS because the Proceede preamp decodes DTS and DD5.1.

So I guess I need to find a way to output a DD5.1 signal over spidf when I'm playing doom3 if I want surround sound. I can't hook up 3 minijack to RCA connectors to make a 5.1 signal to the preamp. As for hooking them up to the amps... I may have to look into that.

All I want is 1800W 5.1 doom3, is that so hard? :->
 
Does D3 output a 5.1 signal? I'm not sure since I don't have a copy to look at but since the DVD plays fine then I'm thinking that nothing is wrong with your setup....execept that it's Intel ;). (lol) Try setting up the Sound options in D3 for 5.1 if you can.

Look into AC3 filter, the newest version adds an option to encode everything into 5.1 like with Soundstorm. I haven't tried it since I do have a Soundstorm board so good luck.
 
can you tell me what model amp you have that outputs 1800W (i call BS)? Thats pretty crazy and im waiting on your/your dad's pics. But yes the only for 5.1 is soundstorm, you can get analog 5.1 using Aud2 w/ mini to rca outs running to your pre's 5.1 or 7.1 inputs.
 
i always thought certain C-media soundcards re-encoded to DD5.1 via software. Now in your case you would need one that came with an optical out daughter card but it may be worth a look around.

Don't forget many different brands use the c-media chipset so you might have a large selection to weed through (if all i'm saying is true).
 
Techguy said:
I fired up our Video Essentials DVD, and set PowerDVD's speaker setting to SPIDF and then I had a 5.1 signal. I can even enjoy DTS because the Proceede preamp decodes DTS and DD5.1.

So I guess I need to find a way to output a DD5.1 signal over spidf when I'm playing doom3 if I want surround sound. I can't hook up 3 minijack to RCA connectors to make a 5.1 signal to the preamp. As for hooking them up to the amps... I may have to look into that.

All I want is 1800W 5.1 doom3, is that so hard? :->
Click to expand...

There are lots of games out there that support Dolby Digital 5.1 but very few, if any, will pass that signal along via the digital output on your computer. Instead, this signal is decoded by your sound card and can only be output via the analog outs. The way most people get 5.1 in games without an Nforce 2 board is to use the analog outputs on their card and run them to the analog inputs on their receiver.
 
computerpro3 said:
can any m-audio cards do it? i think they can...
Click to expand...
I know the revo can't. Unfortunately all the other models are way too pricey and he'd get away cheaper by getting Nforce2 mcp-t and an XP cpu for a nice hardware solution.

As i mentioned prior, i think the cmedia 5.1 cards can encode DD5.1 via software but it'll take some investigation in some sound card and HTPC forums. (im actually curious now since i have one of these laying around)

Edit: heres a cmedia specific forum right here: http://www.3dss-forums.com/cgi-bin/wwwthreads/postlist.pl?Cat=&Board=Forum21

Apparently dolby ac3 support is still in development BUT here's a plug-in that might actually work:
Source: http://www.3dss-forums.com/cgi-bin/...=142326&page=0&view=collapsed&sb=5&o=0&fpart=
Cmedia/Dolby plug-in: http://acidbao.free.fr/isoft/dlpage.php?prog=DolbyOutDS
 
Pics, as promised. Sorry it took so long, mom lost the camera :-/
Rack #1:
img_1921.jpg

Rack #2:
img_1922.jpg

Back of Rack #1:
img_1924.jpg

Back of Rack #2:
img_1923.jpg


The screen, you can kinda see doom3... I couldn't get a good pic of the DLP projection image because I couldn't adjust shutter settings :-/
img_1927.jpg

Theatre lighting :->
img_1926.jpg
 
DruSi3r said:
can you tell me what model amp you have that outputs 1800W (i call BS)? Thats pretty crazy and im waiting on your/your dad's pics. But yes the only for 5.1 is soundstorm, you can get analog 5.1 using Aud2 w/ mini to rca outs running to your pre's 5.1 or 7.1 inputs.
Click to expand...

1800w is easy, when you realize he isn't doing it with just one amp. Using 3 2-channel amps has been a quite common solution for 5.1 HT, especially as there were no multichannel amps from the audiophile manufacturers initially. If I had space and lots of money, I'd probably have monoblocks mated to a very nice preamp/processor, instead, I have no space and a bit of money, so I have a denon 4802, lol.
 
It has been said before but...

Visit Radio Shack and pick up three headphone (1/8" Stereo) to dual (stereo) RCA cables. Hook them up as if you were hooking up a set of 5.1 analog speakers such as the Altec Lansing 251's or similar.

Front L/R, Rear L/R, Center/Sub (Check the IT7 manual for proper connections.)

Connect the RCA's to their respective spots on your receiver's 5.1 block input; a group of female RCA's that are generally encircled or highlighted as being "six channel input" or some derivative thereof.

Most receivers will have that feature, even if they already have DD5.1+/DTS+ decoding built-in. It was a backwards compatibility throw-back for DVD players that had the DD decoders built in and other devices that could output DD via split channels versus optical or coaxial digital.

Set the sound panel on your PC to use analog out to a Dolby Surround speaker setup and your receiver to use the six-channel-input block on whatever category your PC is attached to (VCR2, DVD2, etc.) and you should have surround in your games (and anything else)...
 
Orinthical,
The preamp we have doens't have that feature.. :-/ You get either analog 2 channel inputs, or digital inputs... it's got a ton of digital inputs... And while you can bind analog input 1 and say video input 7 it make out put... VHS, you can't mix multiple audio inputs to make one output, which makes sense.

..and I leave for Tech tomorrow. I'm going to give that plugin a whirl tonight and we'll see if I can get some digital 5.1 doom 3 action. Even without 5.1, it's been fun playing it on the huge screen.

and for the 1800 W, yeah it's 3 600W Harmon/kardon Citation 7.1 amps, we sold the Citation pre-amp and got a Proceed one that does DTS.

I'm not sure what model the projector is, but it's a sharpvision, and looks great as long as there is controled lighting. There are no windows in that room, so outside light isn't an issue. Our lights on the side of the room dim really low, and gives a nice movie theatre feel, without effecting the picture. When the lights are turned on, you can see the scree, but I wouldn't watch TV or movies with the lights on.
 
Ahh well, was worth a shot. G'luck with that plug-in.

Someone has to sell an external converter/DAC (or in this case ADC) to allow the conversion of six channel input to a digital optical or coaxial connection. I tried googing it for a bit but could not find any. Seems like it would be a nice thing to have though.

If I find anything, I'll let you know.
 
I posted this is general mayhem but what the heck.
The sound in this game is awesome. It needs a subwoofer too. You have to play it very loud and in 5.1 to truely appreciate it. You can hear things breathing around you as you peer around the corner, you have only 16 life left. You look around is something behind you? you switch to flashlight looking in every corner. You reload your shotgun, crap only 4 shots left. Them bam you shoot as the enemy lunges at you from under the stairs. You freak and start unloading, you life is draining he's not dying what do you do? run run all of a sudden the red screen appears time to restart. Whoo what a rush. I love this game

Difficulty Veteran (taking turns with my brother lots of saves lol)
Playing on AIW 9700 pro
1280x720 (some stretch) Ultra quality
31fps in time demo some hicups not bad though
monitor Panasonic 50" rplcd tv
Audigy with 6 channel analog out to Denon and subwoofer
 
I played the Alpha at a friends house several months ago (still don't have it myself since I need to upgrade) and the way you described it is exactly what it was like! It's nice to get a game that can scare me alittle after I'm done playing it. :D
 
The only way to get 5.1 from doom 3 is analog hookups or nforce2 sorry. I am using it with a nf2 board through 1200w of infinity speakers and its simply amazing. Start talking to a scientist and just spin around yuo can hear the voice go through all 5.1 channels. Also the bass in doom 3 is very deep but seems to come in at random times to shake the house even when monsters arent around.

http://mywebpages.comcast.net/hayrab/doom3-3.jpg

other pics are in sig
 
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