Email I recieved from Creative about SPDIF

M5AM · 08-15-2005, 11:44 AM

I sent an email to Creative last night regaurding the digital SPDIF output on the regular ZS sound card and how it could be converted to an coaxial plug. Well before I even recieved the email I found exactly what I needed here http://www.ramelectronics.net/html/RCA-mini-spdif.html and bought it.

I got the email back this morning from creative and it had a lot of information in it that I was unaware of. Here is the main part of the email that had me confused I should say.

"CONNECT THE DIGITAL OUT TO A RECEIVER
1. Use a stereo minijack (1/8 inch) to RCA cable.
2. Connect the minijack end into the digital out on the sound card
(This is the furthest port away from the firewire SB1394 connector).
3. Connect the left (white) RCA connector to the SPDIF coaxial input on
your receiver.
4. Leave the right (red) RCA connector disconnected.

SET THE AUDIGY2 TO USE DIGITAL OUTPUT
1. Go to Start > Programs > Creative > SB Audigy 2 > Surround Mixer
2. Click on the (+) above the main volume control.
3. Make sure there is a check next to "Use Digital Output Only"
4. Please also verify this under start > run > SNDVOL32 > advanced

DISABLE AC3 DECODING
1. Go to Start > Programs > Sound Blaster Audigy 2 > Audigy HQ > Device
Controls > Decoder
2. Select "SPDIF Passthru (Dolby Digital / DTS Digital Out)"

The soundcard will now pass the AC3 signal and raw PCM data to your
receiver to be decoded as 5.1 channel audio.

Please note that only AC3 audio (such as audio from DVD movies) will be
in surround sound. All other audio will be processed by the receiver as
PCM, and thus you will only hear the two front channels. This is due to
the limitation of the S/PDIF connection allowing only 2 channels to
cross over a single wire. More information about this can be found at http://www.dolby.com.

Note: There are audio options within the DVD software that need to be
configured for Dolby Digital pass-through. These options are different
depending on what software you have. If you need clarification on what
needs to be enabled or checked, then reply with all the options
available under Audio properties within your DVD software.
"

Let me know your thoughts and if there is anyway around this.

RedGTiVR6 · 08-15-2005, 12:05 PM

bump! cause I'd like to know!

DRWeside · 08-15-2005, 01:23 PM

Quote: Originally Posted by M5AM

I sent an email to Creative last night regaurding the digital SPDIF output on the regular ZS sound card and how it could be converted to an coaxial plug. Well before I even recieved the email I found exactly what I needed here http://www.ramelectronics.net/html/RCA-mini-spdif.html and bought it.

I got the email back this morning from creative and it had a lot of information in it that I was unaware of. Here is the main part of the email that had me confused I should say.

"CONNECT THE DIGITAL OUT TO A RECEIVER
1. Use a stereo minijack (1/8 inch) to RCA cable.
2. Connect the minijack end into the digital out on the sound card
(This is the furthest port away from the firewire SB1394 connector).
3. Connect the left (white) RCA connector to the SPDIF coaxial input on
your receiver.
4. Leave the right (red) RCA connector disconnected.

SET THE AUDIGY2 TO USE DIGITAL OUTPUT
1. Go to Start > Programs > Creative > SB Audigy 2 > Surround Mixer
2. Click on the (+) above the main volume control.
3. Make sure there is a check next to "Use Digital Output Only"
4. Please also verify this under start > run > SNDVOL32 > advanced

DISABLE AC3 DECODING
1. Go to Start > Programs > Sound Blaster Audigy 2 > Audigy HQ > Device
Controls > Decoder
2. Select "SPDIF Passthru (Dolby Digital / DTS Digital Out)"

The soundcard will now pass the AC3 signal and raw PCM data to your
receiver to be decoded as 5.1 channel audio.

Please note that only AC3 audio (such as audio from DVD movies) will be
in surround sound. All other audio will be processed by the receiver as
PCM, and thus you will only hear the two front channels. This is due to
the limitation of the S/PDIF connection allowing only 2 channels to
cross over a single wire. More information about this can be found at http://www.dolby.com.

Note: There are audio options within the DVD software that need to be
configured for Dolby Digital pass-through. These options are different
depending on what software you have. If you need clarification on what
needs to be enabled or checked, then reply with all the options
available under Audio properties within your DVD software.
"

Let me know your thoughts and if there is anyway around this.

What part is confusing you? What's confusing me is:
3. Connect the left (white) RCA connector to the SPDIF coaxial input on
your receiver.
4. Leave the right (red) RCA connector disconnected.

I thought that digital coax cables only had one pair. This implies that you can use regular RCA cables.

RedGTiVR6 · 08-15-2005, 01:32 PM

that's one thing that caught my eye too, but I thought I just wasn't reading it right or just didn't get it.....

digital coax is just a single RCA end isn't it?

M5AM · 08-15-2005, 01:43 PM

Yeah it is but from what I heave read it a digital coax and standard coax are the same thing. The only difference is the impedance level on the cable its self. The digital coax has a 75ohm impedance and the standard coax is 50ohm.

Here is a site I found discussing that. http://forum.ecoustics.com/bbs/messages/5/1370.html

What I am confused about is the fact that by playing regular MP3s through the computer into my headunit I will only recieve 2 channel sound, and doesnt that mean that only my front channel will work and I will not have a sub or anything like that? Or did I missunderstand that. Because I am under the impression that my 1 channel is front driver and 2 channel is front passenger.

DRWeside · 08-15-2005, 01:56 PM

That's what I thought. I'll have to mess around with that some more. I had purchased a digital coax cable, but after trying tons of different settings, I couldn't get my receiver to play any music from the digital input. Hopefully, I still have that cable around.

DRWeside · 08-15-2005, 02:02 PM

Quote: Originally Posted by M5AM

Yeah it is but from what I heave read it a digital coax and standard coax are the same thing. The only difference is the impedance level on the cable its self. The digital coax has a 75ohm impedance and the standard coax is 50ohm.

Here is a site I found discussing that. http://forum.ecoustics.com/bbs/messages/5/1370.html

What I am confused about is the fact that by playing regular MP3s through the computer into my headunit I will only recieve 2 channel sound, and doesnt that mean that only my front channel will work and I will not have a sub or anything like that? Or did I missunderstand that. Because I am under the impression that my 1 channel is front driver and 2 channel is front passenger.

I think you misunderstood.

Your headunit should have a digital input. If this is not the case, then you won't be able to use the SPDIF-out on that soundcard.

Maukio · 08-15-2005, 02:14 PM

Quote: Originally Posted by DRWeside

What part is confusing you? What's confusing me is:
3. Connect the left (white) RCA connector to the SPDIF coaxial input on
your receiver.
4. Leave the right (red) RCA connector disconnected.

I thought that digital coax cables only had one pair. This implies that you can use regular RCA cables.

Well, I think what you are confused about is ideally you want to use this cable just like M5AM said. Creative tells him in the e-mail reply to use a stereo cable. It would be just like this but with two contacts on the mini side and two RCA connectors on the other side. One of those two sides (the red they say) is basically useless when you use a stereo cable.

DRWeside · 08-15-2005, 02:46 PM

LOL

The answer to my question is that the difference is in the impedance between analog and digital cables.

The answer to his question is not so clear, because he hasn't said what make and model HU he has in his car.

RedGTiVR6 · 08-15-2005, 02:49 PM

he being the original person starting this thread?

it's an eclipse unit...for the life of me I can't remember the model though.....

DRWeside · 08-15-2005, 03:04 PM

Quote: Originally Posted by Red GTi VR6

he being the original person starting this thread?

it's an eclipse unit...for the life of me I can't remember the model though.....

OK

Quote:

Please note that only AC3 audio (such as audio from DVD movies) will be
in surround sound. All other audio will be processed by the receiver as
PCM, and thus you will only hear the two front channels. This is due to
the limitation of the S/PDIF connection allowing only 2 channels to
cross over a single wire.

I think that the two front channels in this case are referring to the front channels in a HOME theater setup. Am I wrong or wrong?

Edit: A good HU should pass on low frequency sounds to a subwoofer no matter the type of audio being played.The problem you may have is that your rear speakers may not reproduce of the 2 channel music being output by the HU, if they are being used as the surrounds. Again, a good HU should differentiate between the types of audio and reproduce the sound accordingly.

M5AM · 08-15-2005, 10:02 PM

Thanks for the help. It is an eclipse 8454. I will only be running my front components and 1 subwoofer. This a follow email I just recieved.

"I gather you are hoping to have surround output as well from normal
music files playback. Usually for dvd movies, they will have discrete
channels if they support dolby digital.

For digital connection, the CMSS feature on our sound card will not have
any effect for it as it is for upmix during the use of analog
connection.

Unless your speaker system has a speaker system with a decoder for upmix
purposes. You may then set it to upmix from stereo to surround.
Else I'm afraid you will have to stick to analog connection in order to
have surround effect.

To setup the CMSS feature on the software I have included the steps for
you to try out.

TO TURN ON CMSS IN Mediasource
1. Open MediaSource (Start, All Programs, Creative, Creative
MediaSource,
Creative MediaSource Organizer).
2. There should be an EAX button underneath the Record button at the
bottom of the screen, towards the left. Beside this button, there
should be a
small ellipsis button (. . .) that you can press. Click on this.
3. Go to the CMSS 3D tab and check the box next to "Enable CMSS 3D""

RedGTiVR6 · 08-15-2005, 10:18 PM

I'm a little confused then....why are you concerned with surround sound?

M5AM · 08-15-2005, 10:56 PM

I am not concerned with surround. I am not sure why they assume that. I just want stereo sound and want my sub to work with it.

RedGTiVR6 · 08-16-2005, 08:11 AM

I don't see why it shouldn't then....