Can you connect 2 units to 1 dolby digital port??

[toddU]

my aiwa nsx-ds11 shelf system has one optical digital port and one coaxial digital port for connecting to the dolby digital decoder...my dvd player is presently connected to the optical port and i recently had hdtv cable installed from comcast. i tried connecting the motoralla cable box and my dvd player together via an optical toslink splitter into the one optical port in my receiver...no good...only got sound if i disconnected one of the two components...even with the cable box turned off it still didn't work...neither component has a digital coax port...any ideas or is it not possible to connect both components to this shelf system without running 6 cables??

thanks-

[57U]

I'm confused. Audio and Video travel by different cables. You need to connect video cables (usually component video for HD or S-Video for SD) to the TV for each input device for the picture and audio cables (which you say already work)?

[toddU]

i'm just talking audio connections...my video cables for my dvd player and cable box connect to the component #1 and component #2 video ports on my tv...they work fine...
i have an audio fiber optic connection from my dvd to the dolby dig decoder in my aiwa shelf system...that works fine by itself...i wanted to connect the audio port in my hdtv cable box to the same audio port that my dvd plugs into so that i get the dolby 5.1 surround sound from my hdtv stations (all four of them:rolleyes: )...

i connected to two cables from the dvd and cable box into a toslink splitter and then ran one cable from the split into the shelf system...theres no sound from either the cable or dvd when i do this:(

hope this makes more sense...:o

[57U]

Yep, that makes sense. If you have one of those Radio Shack Toslink splitters, they may only work "one way". ie - one in, two outs. Not two ins and one out. You may need to get a toslink switch instead... I always wondered if those RS splitters were "bidirectional"...

Anyone else have any experience?

[toddU]

yup, upon further review, those splitters are indeed 1 in, 2 out...:o

uggh...:o

seems what i want is a toslink switch...a quick google search turned up a 3-port toslink switch (3 ports in, 1 out) for about $20...

appreciate the help...

[KlineKR]

Are you sure they are not bi-directional or are they just labled that way? I know that most RF signal splitters are labled with inputs and outputs but in reality can be used in either direction. I can't imagine what would make a passive fiber optic device directional.

[Ratman]

Originally posted by KlineKR
I know that most RF signal splitters are labled with inputs and outputs but in reality can be used in either direction.

Not true... many are unidirectional. Diodes are used to keep stray signals from 'bleeding' back into the other outputs.

Those that are bi-directional are usually labeled "combiner/splitter" or "hybrid splitter".

[KlineKR]

An RF power divider never has diodes. If that were true it would rectify the signal causing severe distortion. They are passive linear devices comprised of transformers and resistive loads and can always be used in the reverse direction. Besides, that has certainly has nothing to do with a passive optical device.

[57U]

The optical splitter looks like a very simple device which probably uses some form of "mirror" or prism to split the signal from 1 into 2. Perhaps this "mirror" or prism doesn't work in the opposite direction?

Sure would be nice to get a definitive answer on this subject, since it comes up every once in a while.

[KlineKR]

http://www.tpub.com/neets/tm/108-11.htm

[57U]

Thanks for the link.

Although an optical "combiner" looks identical to an optical "splitter", I assume that there are variations in "lens" or "gradient" allowing the light to "escape" the "desired" fibre due to index of refraction/reflection effects, depending on whether it's a directional or symetrical coupler.

[57U]

Did a search for combiners and found a couple. Here's an example.

http://www.soundprofessionals.com/cgi-bin/gold/category.cgi?category=220&item=SP-TOC-SPLIT&type=store

Also read an article from someone who said he used the RS splitter as a combiner...ToddU, you may wish to give it another try, but make sure you have only one component turned on at a time...

[Ratman]

Originally posted by KlineKR
An RF power divider never has diodes.

I'm not an electrical engineer... I may stand corrected on the diode issue.

But I will stand behind my opinion that all splitters do not work as a "combiner" (copper... I can't address optical, but assume that some of the same principles would exist at the consumer level). There are differences.

[mkass]

57U, I have 2 of those splitters which after speaking to the tech rep on the service line from the place which I bought them, I think it was audiomidi.com or cablestogo.com cant remember, cant find the receipt, but I use it to connect my DVD and PC to the same input on my HT receiver, only caveat is I can't have them both sending signals to the receiver at the same time, or no sound, If I disable the optical output from the PC, the dvd plays fine, if the dvd is off and I turn the pc optical output back on, I can listen to mp3s thru winamp to my hearts desire at really loud volumes..hehe


mkass

[Paleface]

toddU, why do you need to split the signal? Can't you hook the HD cable via the open coax input?

Some argue if there really is any benefit to using optical connections over coax anyway.... reflected light inside the fiber lends itself to "jitter".

Do you have something connected to the coax?

I had a similar problem with my low-end Pioneer receiver and I found in the setup where I can designate the optical and coax to the component I want. So, right now, I have my DVD via optical, and my HD cable via coax.