Output of DB5.1/DTS Audio

[moamoa]

I have built a HTPC around SageTV and an ABIT iL-90MV motherboard, since it has a S/PDIF optical audio out.

However, I do not appear to be able to get true Digital Audio out from this setup when playing a DVD, even though it has an Optical Digital port.

I have a very good Yamaha surround sound amplifier that supports Dolby Digital and DTS and has an Optical Digital port. Previously I would connect my standalone DVD player to this and get awesome sound.

The amp has a display on the front that show the feed it is receiving. When playing a DVD it typically shows "ProLogic" while the trailers are on as this is the default setting, but as soon as the Movie would start or a THX trailer came on, it would switch to DTS or Digital as it detected the stream. Great! I would have expected the same when playing a DVD via SageTV, but this does not happen.

This is how I know my SageTV setup is NOT outputting the raw digital feed from the DVD. I have set the Realtek up to output "Digital PCM Output" through the P/SDIF, yet the amp still shows "ProLogic" even when I know the DVD is really outputting 5.1 or DTS.

This now appears to be a complete downgrade from just having a $30 DVD Player with optical out. So, I'm desperate to resolve this.

How can I get this raw digital feed to my amp correctly?

I attach a copy of the DVD audio rendering options I have, I have tried them all and non work as should.

[ben_95sl1]

Your problem is probably that you have not setup spdif with the dvd audio decoder, which is also necessary. If you have the nvidia decoders, then you need to make sure those decoders are the default decoders, then call out the default decoders in sagetv, and then play a movie with 5.1. The nvidia audio decoder icon should then show up in the tray (go into it and setup to pass 5.1 through spdif)...if it doesn't, then using radlight filter manager, you find the nvidia audio decoder and then edit the properties, which I believe also works fine. There is a longer more helpful post on this forum which better describes how to setup nvidia decoders, as I was very brief.

If you don't have nvidia decoders, it can still easily be setup, it's just different.

Good luck....

[dflachbart]

Also, be aware that you won't get any DTS to your receiver if you are not running your audio setup in bit-perfect mode. This means

1) bypassing the internal Kmixer component of Windows which is resampling everything and destroying the DTS signal, e.g. by using ASIO or Kernel streaming

2) having a sound card that does not do hardware resampling to 48khz like e.g. the Soundblaster cards. Don't know about the Realtek, I am using Chaintech AV-710 which works great.

Here's a link with some more info on ASIO/bitperfect playback from the AVS Forums

Dirk

[stanger89]

Originally Posted by flachbar

Also, be aware that you won't get any DTS to your receiver if you are not running your audio setup in bit-perfect mode. This means

That really only applies to DTS CDs, it's a weird issue with 44.1k DTS in wav files, and also DD in wav files, everybody points fingers at each other for that problem.

You don't need to do anything special for DVDs though, that audio is handled correctly by default. No need for special cards or Kmixer/ASIO for DVDs.

[dflachbart]

Originally Posted by stanger89

That really only applies to DTS CDs, it's a weird issue with 44.1k DTS in wav files, and also DD in wav files, everybody points fingers at each other for that problem.

You don't need to do anything special for DVDs though, that audio is handled correctly by default. No need for special cards or Kmixer/ASIO for DVDs.

Ah ok, then I stand corrected... I assumed DTS would be 44.1k in general

Dirk

[stanger89]

Well there's really two issues. First off though, DVD audio is 48kHz by default, also Windows recognizes DD/DTS in DVDs as data and handles it correctly.

But the other issue is that for DD/DTS in wav files (CDs) is not regognized as data, and is instead treated as PCM.

[moamoa]

Working fine with the Nvidia codec and P/SDIF out!

I'm still using the 30 day trial version. Which flavour do i need to buy? Is the basic one good enough, or do I need the ones with all the Audio features, even though I want no PC processing as such, just pass through?

[lobosrul]

I belive the only difference between gold and platinum is DTS decoding.

Correct my if im wrong here, but Purevideo's sound decoding doesn't work with Sage. I though it was a bug until I read the fine print, it only works with WMP. Maybe it does pass thru though.

I've had the best results with AC3 filter. But I'm decoding to 2 channel.

[stanger89]

All you need it the Bronze.

Passthrough works just fine with nVidia's decoder, it's decoding that's disabled in non Dolby-Certified apps.

[toricred]

What audio renderer are you using when using ASIO4ALL? Have any of you tried the flash upgrade to the 710 to allow hardware ASIO?