Surround audio for video help
 

Hi folks. I've been around on the site, but I am new to the audio area (and audio production in general).
I want to teach myself some 5.1 mixing that I may be able to incorporate into my video work. I've read the FAQ and searched in this forum for the last two hours and I am thoroughly confused.
I suppose I will tell you guys what I've done so far, and what I want to do. It will be clearly evident that I am very new at this sort of thing.
I'm using Audition 3 and experimenting with mono tones in the surround encoder. In my PC I have a sound blaster audigy card running coaxial S/PDIF to a Sony consumer 5.1 reciever.
I should be able to hear each channel independently with this setup, no?
I can't - the system does stereo fine, but does not output the surround channels (RL,RR,LFE).
I'm guessing that the reciever is expecting a Dolby Digital (AC3) stream. Probably Audition wants to output 6 discreet mono channels and the receiver can't handle that.

If my instincts are correct I'll probably have to ditch the receiver and set up the sound card to output those channels independently. Since I'm still learning this I'd like to spend as little as possible on new hardware if I need it. However, if it is something that may be a good investment - I would consider it.

I'd be much appreciative if anyone can point me in the right direction here. Thanks.

I'm not completely certain with your setup but yes, the Spdif only carries 2 channels so you would need to be spitting out an AC3 for it to work. To monitor your mix properly you need to have discreet outputs for each of the channels as you mention. Lots of good info here:
Post Production forum! - Gearslutz.com
John.

I use Soundblaster audigy with a 5.1 PC speaker (logitech and Creativelabs are making some for cheap). The output is the 3 minijack at the back of the card.

With Acid software, I move 5.1 sound in realtime with a mouse or joystick.
Then you can encode in AC3 for your DVD.

The soundblaster and some software require the special driver including ASIO in order to work. I think Asio is not always installed by default with the audigy drivers.

you really don't want to mess around with consumer 5.1 setups, at least not the cheap ones. you want 5 matched speakers ( self powered is ok ) or the appropriate amps(s) and passive speakers. add in a subwoofer.

there are many good FW / USB2 / PCI audio interfaces that have 6+ discreet outputs. get away from the consumer stuff. its possible you could pull the entire setup off for maybe $1k or so. thats not super quality, but good enough for most folks until you learn to hear the difference.

Giroud is correct: you need to find an ASIO driver for your soundcard. This will enable you to direct each mono channel within Audition to a separate output (which are then accessed via the 3 stereo minjacks at the back of the card, not by the spdif).

There are freeware ASIO drivers on the web for your Audigy card (and even for SBLive 5.1!) but for $200 you could use a Presonus Firebox, which has better quality and TRS ports to link to your powered speakers, or to analogue 5.1 inputs on a receiver.

Thanks for the responses everyone!

Yeah - I figured that the S/PDIF was where I was going wrong. This particular receiver does not have analog 5.1 inputs so I'll have to find another solution. Perhaps a set of 5.1 computer speakers should do for now. Once I get better at this and plan on making money mixing audio I'll certainly upgrade, but right now I just want something that works.

For learning and getting your chops up there's no reason a good 5.1 computer setup can't work. The Logitech setup was once sold by Alesis and I used that to get my first job done; the sub doesn't set up properly, always a bit too hot but fine for learning. Don't forget the importance of calibrating your room and the surround setup, absolutely crucial. At a minimum you'll need a Radio Shack analog SPL meter and you can follow the instructions here:
NEW UPDATED Room Calibration for Film and TV Post - Digi User Conference

Did I mention that this is very important?!

I mix and edit 5.1 surround very nicely with a low cost set up - though I am on a Mac.
I use a Focusrite Saphire (firewire) which gives me 5 outputs into an M-Audio 5-speaker surround monitors. Very simple to set up. I can test that each monitor is giving me the correct track output (ie, right, center, left etc).
I mix using Soundtrack Pro (Final Cut Studio) which is native surround sound. You output to Dolby AC3 surround format.