What is SPDIF and how to I use it?

[msmith8228]

What does "SPDIF" stand for?

I believe that it will allow me to use Sage to playback and reproduce 5.1 Dolby Digital sound via my Home theater sound system with a coax / fiber connection from my computer to the receiver -- is this correct? I understansd that the source recordings in Save will have to be 5.1DD.

How to I enable this SPDIF output (pass-through?) on my sound card -- (which is motherboard based -- a very new E-machine with a AMD 64 3400+) or do I have to add a dedicated sound card if this option is not supported with the onboard sound system. If I have to add a dedicated sound card which model would everyone recommend?

Final question -- do I need to use the AC3 filter -- download or the filter that comes with version 4.0 to get this to work?

MJS

[lovingHDTV]

I'll give this a shot.

I don't remember the definition of SPDIF google it if you want the name.

1. You need a reciever that can decoded 5.1 digital sound. Sounds like you have that.
2. You need an spdif output from the computer. I have one integrated on my Nforce MB that I use. They can be electrical (coax) or optical (fiber). My MB has both. Just make sure that you MB or sound cards output has the format you need with your reciever.
3. You need an audio decoder that allows for SPDIF passthrough. I believe that they all have this now, at least all the ones I've looked at do.
4. You must enable the SPDIF output on the MB/sound card and in your audio decoder. This is device/decoder dependant. On my MB I set it up in the BIOS settings. On the Sonic decoder there is a button you hit under the configurator to enable it. For default sound drivers you can enable it through the sound mixer in windows. It is called 'digital only' I believe under the advanced options. For AC3 I had to play around with this a little. As the filter shipped with Sage is not a "full" install you don't get the AC3 configuation tool so I started filtergraph, dragged a recording onto it, then right clicked the ac3 box and changed the settings for SPDIF passthrough.
5. After it is enabled hook it up to the reciever and check that it is decoder the digital signal.

You do not have to use AC3 filter, just any audio decoder that supports passthrough. AC3 filter does have some good points, but has it warts also. It is free though

If you want more details on my AC3 setting let me know and I'll go write them down. I get 5.1 sound on all recordings from my A180 and PVR250. It is quite nice in that you can watch it play the files and see what it is recieving on its inputs and what happens on the outputs.

hope this helps a little,

[msmith8228]

I did a Google search and the definition for S/PDIF is 'Sony / Philips Digital Interface Format'

MJS

[shawncochran]

Originally Posted by lovingHDTV

...so I started filtergraph, dragged a recording onto it, then right clicked the ac3 box and changed the settings for SPDIF passthrough.

Filtergraph? I've got the SPDIF working on everything for my audio (only a receiever being used here) but I can't get DD5.1 out of Sage. I can out of any other app, but not Sage. Thoughts?

[stanger89]

In AC3Filter, Go to the System tab, and check the DD and DTS boxes in the SPDIF passthrough area. And then in SageTV set AC3Filter as the Audio Decoder for DVD (note that there's a separate setup area for DVD).

[JasonJoel]

Of course, one more piece of clarification is that regular TV recordings will NOT have 5.1 sound. Probably obvious, but I thought we should be clear.

HD recordings would have it (if the source does), and obviously any other recordings you already have that contain 5.1.

But the hauppauge TV tuner cards will not record 5.1.

Jason

Originally Posted by msmith8228

What does "SPDIF" stand for?

I believe that it will allow me to use Sage to playback and reproduce 5.1 Dolby Digital sound via my Home theater sound system with a coax / fiber connection from my computer to the receiver -- is this correct? I understansd that the source recordings in Save will have to be 5.1DD.

How to I enable this SPDIF output (pass-through?) on my sound card -- (which is motherboard based -- a very new E-machine with a AMD 64 3400+) or do I have to add a dedicated sound card if this option is not supported with the onboard sound system. If I have to add a dedicated sound card which model would everyone recommend?

Final question -- do I need to use the AC3 filter -- download or the filter that comes with version 4.0 to get this to work?

MJS

[stanger89]

Originally Posted by JasonJoel

Of course, one more piece of clarification is that regular TV recordings will NOT have 5.1 sound. Probably obvious, but I thought we should be clear.

Interesting factoid

If you set ac3 filter to 3/2+SW 5.1 and check the S/PDIF box, it will expand TV recordings to 5.1 and then encode it to DD

Also note, the S/PDIF box on the Main tab forcess AC3Filter to always output a DD signal, encoding as necessary.

[JasonJoel]

*sigh*

Ok, you're right. That is cheating though. Really that is just stereo or pro logic that was re-encoded to 5.1, not originally mastered 5.1.

That is interesting though. I didn't know it did that.

Jason

Originally Posted by stanger89

Interesting factoid

If you set ac3 filter to 3/2+SW 5.1 and check the S/PDIF box, it will expand TV recordings to 5.1 and then encode it to DD

Also note, the S/PDIF box on the Main tab forcess AC3Filter to always output a DD signal, encoding as necessary.

[stanger89]

Wasn't attempting to correct you, just throwing out an interesting factoid

FWIW, I don't really see the point, as I don't know what algorithm AC3Filter uses, and I'd guess DPL II on the reciever would be better.