Digital Audio output jack on the back of CD/DVD drives

[dieselstation]

what's that for? how do i use it? do i need a special cable? does it plug into your sound card? I'm talking about the Digital Audio Out jack, not the Analog Audio out.

 

[BCYL]

I never used it... I just left it unplug and still get Dolby digital 5.1 sound out of my DVD decoder card...

 

[AndyHui]

The digital audio out is simply an SPDIF connection for CD music output from the CDROM/DVDROM/CDRW. You can use this as an alternative to the analog connection. Supposedly the quality is better, but no-one can seem to hear the difference.

Since most recent soundcards only have one CD-In, but also have the Digital CD-In, you can connect two CDROM/DVD/CDRWs to the soundcard so that you can play CDs from both drives.

As above, this is only for music CDs played in the drive; this has nothing to do with CDROM/DVDROM/CDRW content, such as movies, MP3s, wavs, Dolby Digital.....

 

[Eug]

<< The digital audio out is simply an SPDIF connection for CD music output from the CDROM/DVDROM/CDRW. You can use this as an alternative to the analog connection. Supposedly the quality is better, but no-one can seem to hear the difference.

Since most recent soundcards only have one CD-In, but also have the Digital CD-In, you can connect two CDROM/DVD/CDRWs to the soundcard so that you can play CDs from both drives.

As above, this is only for music CDs played in the drive; this has nothing to do with CDROM/DVDROM/CDRW content, such as movies, MP3s, wavs, Dolby Digital..... >>


If you connect the SPDIF out directly to your stereo system the sound quality is significantly better than analogue, but I'm saying this having tested on a full-fledged stereo system with higher end tower speakers. But even with a high quality computer sound system, even: digital out on DVD-ROM --> digital in on sound card --> digital out on sound card --> sound system, should sound better than analogue.

By the way, connecting the CD-ROM SPDIF out directly to a standard stereo system with SPDIF in is potentially problematic because the voltage is incorrect. (I don't know much about electronics, but as far as I remember it's 0 - +5 V for CD-ROMs vs. the -0.5 - +0.5 V for receivers.) Most of the time it should work, but sometimes it won't. (It worked with one of my systems and I got this weird pulsing sound on another.) Theoretically it's also possible to fry your stereo system, but so far I've not heard of that happening. The voltage issues are generally irrelevant for computer sound systems though.

As for hearing the music off CDs, I'm sure you're already aware that for most Win 2000 and XP setups you don't need either the analogue or the digital out.

 

[Goi]

The digital cable deliver's S/PDIF output to your soundcard, in digitized form, so that your sound card does the DAC instead of your CD-ROM drive. Because of the noisy environment of your PC, in theory, the longer the signal stays in digital form the better, since it will be less susceptible to noise compared to if it was in analog form. As for audible differences, its up to the quality of your soundcard, the sensitivity of your ears at picking up differences, and the quality of your speaker system obviously.

Additionally, most CD-ROM systems now are able to output digital audio via the IDE bus, so you might be getting digital sound from your CD-ROM even if you aren't using the special digital S/PDIF cable.

 

[Raspewtin]

"Additionally, most CD-ROM systems now are able to output digital audio via the IDE bus, so you might be getting digital sound from your CD-ROM even if you aren't using the special digital S/PDIF cable. "


so if i have no cable going from my cdrom to my sound card. i am definitely getting digital audio correct? (i mean if i can hear it?)

 

[Goi]

Well, yes, if you can hear it and you didn't connect your CD-ROM to your soundcard, then audio from the CD-ROM is output to your soundcard in digital form via the IDE channel to the PCI bus, since this is the only connection from your CD-ROM to your soundcard. It is then converted to analog form on your soundcard's DAC and output to your speakers, unless you have an external processor connected with a digital cable to your soundcard.

 

[AndyHui]

Actually, you need WinME, Win2K or WinXP to transfer audio data over the IDE cable.

You need to set Enable CD Digital Audio For This Device in the Device Manager.

 

[Goi]

Hmmn, Andy, I didn't know that. I seem to be able to output digital audio with my CD-ROM despite the lack of an S/PDIF cable. Unless I'm grossly mistaken, using EAC I can rip CDs digitally, and I'm assuming its through my IDE channel since I can't think of any other digital means of transferring the data out of my CD-ROM drive.