ac3 passthrough doesn't work on audigy2

floyd

I posted another thread on this a week or two back: 0 responses.. I was hoping the new 3533 release would solve my problem but no dice. Has anyone got ac3 passthrough working with a similar config to the one below?

I have a very simple setup: audigy2 oem connected with coaxial spdif to a yamaha amp under win2k sp3. Digital out works fine, save for ac3 passthrough. I either get very choppy audio (sound cutting in and out once a second) or no audio at all when using ac3filter or intervideo to output the ac3 to the spdif. At no time does the Dolby Digital sign light up on my amp either, which is a bad sign. I played with a bunch of spdif options in the mixer and none helped. A small ac3 sign does appear over the taskbar when playing though. Also ac3 passthrough worked on the creative drivers, so its not a hardware problem.

What gives? Do I need some special dsp config? If I get this working the kx drivers would be almost perfect . Thanks for any help/advice.

Eugene Gavrilov

3533b release should support ac-3 passthru
in the mixer, toggle 'ac-3 passthru' option 'on' before starting any of your audio applications
now launch your ac-3 - capable player and set it to 'spdif' mode

when you start playback, you should see a splash 'ac-3 passthru' in the right bottom corner
(if you open kxmixer's 'voice analyzer' during playback, you should see two red strips)

make sure you are using the correct spdif output

if all this fails, reset 'global settings' and 'device settings' and reboot

/Eugene

floyd

Thanks for the reply Eugene.

Well I've tried setting the ac-3 passthru to SPDIF 1, 2, and 3. None work. Whats the difference?

Quote:

when you start playback, you should see a splash 'ac-3 passthru' in the right bottom corner (if you open kxmixer's 'voice analyzer' during playback, you should see two red strips)

Yes, I see the splash screen. And the analyzer shows two red strips. Still either no audio (with ac3 passthrough set to 1 2 or 3) or extremely choppy audio (ac3 passthrough set to off)

Quote:

make sure you are using the correct spdif output

What does this mean? I'm using a miniplug to coax adapter going to my yamaha amp. Isn't there only one possible output to connect the miniplug to? Or do you mean adjusting something else in the mixer?

Quote:

if all this fails, reset 'global settings' and 'device settings' and reboot /Eugene

Just tried this, same results after resetting and rebooting. Any other ideas? :/

Eugene Gavrilov

SPDIF 1 is 'coaxial/optical' output. you probably need this one

please do the following: start ac-3 playback (in passthru-mode), make sure the 'ac-3 passthru' splash is shown, and then open 'i/o status' window (kx tray -> settings -> io status)

copy & paste the content of the window to your posting

/Eugene

floyd

Ok here it is:

SPDIF Inputs:
spdif A: unused
spdif B: unused
spdif C: unused or same as B
[R-Rate Locked; S-Stream Locked; V-Valid Audio]

SPDIF Outputs:
0: 2108506 1: 2108504 2: 2108504 (@48000 Hz)

Eugene Gavrilov

everything seems to work correctly (at least for the driver part)

let's try again

reset settings
reset global settings
set 'digital output only mode' = ON
when in 'digital output only mode', turn off 'swap front & rear' option
set 'surrounder' into 'direct path 5.1' mode
set 'ac3 passthru' to 'spdif1'
open 'speaker test' application
make sure 'front left' & 'front right' are audible and 'rear left & rear right' aren't
open 'IO Status'
(note: all the outputs should be 2108504)
start any ac-3 aware application
start playback
(note: first output should become 2108506 and you should see 'ac-3 passthru' splash)
open kxmixer's 'voice analyzer' page -- there should be two red strips

this should work
if not, let me know

/Eugene

floyd

Thanks again for the help Eugene.

Well i still get no audio. I get all the results you'd expect (io status and test speaker results) but no ac3 audio. I followed all the steps except one:
set 'digital output only mode' = ON
which I can't find in the mixer. In the spdif page I have the top row of buttons with just surrounder on it, next row with front/rear toggle, headphone toggle, and spdif bypass toggle, and lowest row with ac3 decode, ac3 passthrough, passthrough hz, and direct spdif recording toggles. Where can I find the digital output toggle?

Eugene Gavrilov

>> Where can I find the digital output toggle

oops! I forgot this feature was removed for audigy2-based boards...
(because there's a separate 'digital out' connector)

=====

well, I've tested ac-3 passthru for audigy1 and audigy2 platinum ex (both on-board digital out and audigy drive's coaxial out) -- and everything seems to operate correctly
I don't have the original audigy2 platinum board, so I cannot test it

at the moment I don't have any ideas on solving this issue
you've mentioned that you have already tried all the spdif outputs (1,2,3)...
(btw, the 'i/o status' should change accordingly when you switch them)

is there anybody else experiencing the same problem with audigy1/audigy2 and ac-3 passthru?

/Eugene

Canuck

I have been trying to get AC3 passthru working for some time with no luck and now the amp with the external AC3 decoder has packed it in. I do however have a scope and I just bought the special 4 pole mini-jack for digital output and this is what I see when I scope the digital outputs when playing a DVD with WinDVD on my system:

Regardless of the AC3 setting (ie OFF SPDIF1, SPDIF2 or SPDIF3) it appears like there is a valid signal on the tip and the first ring. Ring two looks like an AC3 signal with no data, just a constant sync stream. I can't confirm if the data I am seeing is valid AC3 but the data on tip and ring1 does respond to the pause button on the player. In the paused mode the data stream looks the same as the data stream that is always on ring 2 regardless of whether the player is paused or not.

My configuration is similar to floyd's:

kX Project
Expanding the Potential Exponentially
www.kxproject.com
----------------------------------------------------
kX Audio Driver, kX Mixer (Debug)
Copyright © Eugene Gavrilov, 2001-2003.
All Rights Reserved
Version: 5, 10, 00, 3533 - debug
Compiled: May 21 2003 01:22:22

----Hardware / Software configuration---------------
Driver Name:kX Audio Driver (Debug)
Driver Date: May 21 2003 01:15:53
Driver Version: 5.10.00.3533 - debug
DB Name:none
SB0240o 10k2 [dc00]
PCI Information:
Device: 41102 Subsys: 10071102 ChipRev: 4
Card is '10k2'
Card has MPU device
Card model is '5.1'
Card is Audigy2-compatible
Card HAS AC97 codec
Codec name: SigmaTel STAC9721/23
3D Extension: SigmaTel 3D Enhancement
Codec is 2.0 compliant
Capabilities[6940] :
DAC resolutions : -16-bit- -18-bit-
ADC resolutions : -16-bit- -18-bit-
Ext Capabilities [200]: -slot/DAC mappings-
Port: dc00 Irq: 10
Playback buffer: 20a0
Record buffer: 4000
Number of AC3 buffers: 6
Tank memory: 256 kb
GSIF buffer: 512 samples
OS version: [2 5 0 Service Pack 3; 2 5 0 Service Pack 3; 156 148]
----------------------------------------------------

floyd

Well thanks for trying Eugene. I'm out of ideas at my end. I need the kx drivers for my music production but its a drag that I can't watch ac3 movies Searching the forum for ac3 problems it doesn't seem I'm the only one either.

Canuck: any way you can reinstall CL drivers and use that fancy scope to test them? If all is well with those then there is indeed something fishy with kx's ac3 passthrough...

Eugene Gavrilov

you can always use 'multichannel audio' playback instead of using driver's ac-3 capabilities
(thus, the decoding will be performed by your dvd application)

/Eugene

floyd

well then I can't use spdif output... And I trust my yamaha's sound quality more than the audigy2.

Eugene Gavrilov

you can use three digital spdif outputs (if your yamaha has three inputs, of course)

/Eugene

Max M.

hehe, it's too simple - i'd wonder if at least one of "receivers" has more then one digital input...

Canuck

Since we are on the subject, what determines whether we get PCM or AC3 output on the three outputs of the orange digital output mini-jack of the Audigy2 card? I have assumed that the AC3 passthru plug-in had to be enabled in the DSP and that the drop down list box directed the AC3 stream to the selected SPDIF out.

If that is correct, what signals are being routed to the two SPDIF outputs that are not selected?

Floyd, I'm reluctant to load the Creative drivers until I get my external decoder going so that I can tell for sure what signal I'm getting. On the scope I can't "see" the difference between a PCM signal or an AC3 signal. Parts are on their way so I'm hoping about a week.

Thanks,

Canuck

floyd

Unfortunately only one digital input per sound source here. In fact I don't think receivers are made with multiple digital ins (maybe the $2000-5000 ones)

psmith

I have the exact same problem. Audigy 2 platinum and SPDIF pass through does not work.

Previosuly Eugene said: "at the moment I don't have any ideas on solving this issue". Is this still the case? Is there any chance that we'll get this fixed soon? I tried 3534a and it still doesn't work.

By the way, I'm new to the kx project and I think it's awesome! Thanks guys!

Nias

I've tried the same procedure with my SBLive 5.1 and get the same results, no ac3 pass through to my external receiver.
But my SPDIF Outputs differs from floyd's one.

0: 2109206 1: 2109204 2: 2109204 (@48000 Hz)

is it possible to get ac3 pass through working with a sblive 5.1 and 3533 Drivers?

btw the splash screens come and go the whole time i've played the test ac3 movie.

Nias

Kwake

Hello, I've just recently installed the Kx Project drivers to obtain better ASIO latency in Sonar. However, not being a very serious musician I use my computer mostly for DVD movie playback - and require AC3 passthru to work with my Creative Labs SB Audigy 2 card via the digital SPDIF coax output.

I get the same problem reported by floyd and Canuck and wonder if you will be addressing this issue any time soon? I'd really like to keep using these drivers however would not be able to if this problem isn't fixed.

Please let me know your plans.

Thanks very much,
Kwake

floyd

hmm well it seems the problem isn't isolated to my setup in particular...

Eugene, I realize you don't have perfect capabilities for ac3 testing (I think I read in another thread you have no ac3 amp) but there are plenty of people here willing to test any ideas you can come up with re: fixing the ac3 in kx drivers. thanks again.

Kwake

I second that! I would be happy to help test any potential solutions.

Again, I think your driver has far better overall sound quality than the actual Creative Labs driver. I am hoping that I can include it soon into my C: partition Norton Ghost backup, however for now the Creative Drivers must remain until AC3 Passthru via Audigy 2 is fixed.

Best regards,
Kwake

Eugene Gavrilov

btw, does anybody have hardware that has any indication showing the incoming signal is [dolby digital / ac-3] encoded?
if yes, is it shown when you try to playback ac-3 content?..

that is, there are at least three levels of indication:
1. 'ac-3 passthru' splash displayed by the mixer in the right bottom corner
2. '2109206' spdif status displayed by the 'i/o status' dialog box
3. any indication lamp located on your speaker set / decoder

also try all possible spdif outputs (1,2,3) (on the main page of the mixer) and try all the digital-out connections [digital front, digital rear, digital center+lfe] (located on the back of the card)
also try the 'coaxial out' connection located on the audigy2 drive

make sure you are using 3534a version of the driver

reset settings before your tests

/Eugene

Kwake

Eugene Gavrilov

>> There is only one digital output that I know of on the Audigy2 card (coax

no, there's a 'digital' connector on the back of the card
it is responsible digital front, rear & center+lfe channels
you don't need to switch the card in 'doo' mode in order to get them
(review the details in the Creative manual for your board)

-=-=-

does anybody have -two- audigy/audigy2 boards installed simultaneously?
if yes, please switch one card in 'ac-3 passthru' mode, and another one in 'ac-3 spdif in decoding' mode and check if kX handles the ac-3 streams correctly (well, it works at least for my configuration)
[don't forget to connect both cards! ]

/Eugene

runob

Sorry it doesn't work :'(
The ac3 passthru popup appears (but the weird thing is: this appears even if ac3 is to off), the IO status number changes as they should but my external decoder just won't detect any ac3 stream

I've got a creative SB Live 5.1 + creative DTT2500

None of the spdif channels output anything, and with off I guess the hardware AC3 decoder comes to action. I'm not really experienced with the KX drivers, but in the past with my creative drivers I had to disable hardware ac3 decoding of the soundcard to be able to forward the ac3 stream to my external decoder. Just 2 options: on or off, I suppose that the equivalent in Kx is the ac3 dropbox on the master screen of the mixer?

I read some threads on this board, but are there ppl hat succeeded in passing the AC3 to an external encoder?



My install:

kX Project
Expanding the Potential Exponentially
www.kxproject.com
----------------------------------------------------
kX Audio Driver, kX Mixer (Debug)
Copyright © Eugene Gavrilov, 2001-2003.
All Rights Reserved
Version: 5, 10, 00, 3534 - debug
Compiled: Jun 16 2003 00:15:22

Current skin: Aqua Skin
Skin Author: Eugene Gavrilov
----Hardware / Software configuration---------------
Driver Name:kX Audio Driver (Debug)
Driver Date: Jun 16 2003 00:12:54
Driver Version: 5.10.00.3534 - debug
DB Name:none
SB0060 5.1 [a800]
PCI Information:
Device: 21102 Subsys: 80611102 ChipRev: 7
Card has MPU device
Card model is '5.1'
Card