Question about SPDIF connections.

Stinkfinger75

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I'm getting ready to get a new sound card and a set of Logitech Z-5500 speakers, but the sound card doesn't seem to have the same SPDIF connections as the decoder. This leads to my questions. Does a coax digital signal sound as good as a optical digital signal? Also, the sound card says it has an analog SPDIF output, but the input on the back of the decoder doesn't have the same kind of jack that the output on the sound card has. So, looking at the picture of the back of the decoder, does the SPDIF output on the sound card resemble a normal headphone jack and does the coax SPDIF input on the decoder resemble an RCA jack? If so that means it will need a special cable, can I expect this cable to show up in the sound card box?

I don't want to order the sound card and speakers to find out they're incompatible so I'm doing my research. Do you have anything else to add to this?

Thanks
 

astrallite

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Digital is just 1s and 0s. Coax digital and optical digital should sound the same. In very long cable runs there the audible differences may be time/phase (jitter), but that won't affect the "quality"; since it has yet to be converted to analog, if the cable is well-shielded neither signal will pick up extra noise.

The digital out on the Audigy2ZS is a minijack out. You need a RCA to stereo mini converter (about $7 at Radioshack) to make use of it.

You don't really need to use the digital out, since the Audigy 2ZS will have better DACs than you Logitech Z-5500, so you should stick to analog. Plus the Audigy2ZS can decode DD5.1. The only reason I could see the need for using the digital out would be if the DVD had a DTS track.
 

Stinkfinger75

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So you're saying not to worry about the digital output to the speakers because the card will handle the decoding, and to just hook the speakers up in a normal fashion?
 

astrallite

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Yes.

This also avoids cable switching for games, which will have to be played using analog cables for surround sound, because the X-Fi is not capable of encoding discrete analog channels to a digital medium like Dolby Digital Live or DTS-Connect, resulting in only stereo output in digital mode.
 
Check this card out...it's got a digital coax coming right off the card...no need for adapters, special break out boxes, or extraneous cabling...just digital coax out to digital coax in..nice, clean, simple and with excellent sound quality.
 

xChaoSx

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so if you want surround sound from Gaming you need to go ANALOG? And if you want digital surround sound you're only going to get it from movies, but stereo from games?
 

s3anister

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You <i>should</i> get 5.1 in any application through SPDIF if the app. supports it, you just have to make sure you have everything set up right in the sound driver.
 

Codesmith

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Soundcards can only encode to 2 ch AC3, the sole excepting being the NVIDIA SoundStorm which can encode to 5.1 AC3 and is only avaliable as an integrated sound card in certain NF2 motherboard.

That means that if its prerecorded you get all the channels via SPDIF, but its its not prerecorded content such as a game you only get 2 channel AC3.

So unless you own a Sounstrom Certifiec NF2 motherboard you can't get 5.1 sound from a game using SPDIF.

I believe some creative sound cards actually supported 5.1 AC3 in the form or threee 2channel AC3 digital outputs, which of course was only compatible with a few models of creative speakers.

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BTW I am quite positive that my X-FI has a better DAC then my $350+ Reciever. I am convinced that I am not deluding myself since I assumed it would be the oposite and only noticed the difference after being to lazy to switch back to SPDIF to watch a DVD after a gaming session.

SPDIF is still the way to go if you use integrated audio for music and movies and your equipment supports it.

Oh and Optical vs Electrical doesn't matter. If the signal gets through its perfect, if it doesn't get through 100% of the time, then its then the defects are jarringly obvious (sharp clicks, pops, gaps).

With digital signals there is no room for subtle degradation.