Questions about Toslink's


I'm going to install a new rack at my Dad's house some time this week. As such, i'm going to re-wire his system, which is a 2 channel / HT combo. Due to the large quantity of components involved, i would like to keep things as orderly as possible. As such, i'm trying to keep all the cables just long enough to do point to point wiring. I'll be building most of the interconnects and power cords, so that isn't a problem. What is a problem are the Toslink's that i need.

With that in mind, does anyone know if there is a drawback to running very short Toslink's ? I need one cable in specific that would be about 20" long. This is equivalent to a half meter ( give or take ). Since i can't find any commercial Toslink's at this length, i was wondering if it just isn't a common length or if there is a problem with going this short ? I've found a company that will build me Toslink's of whatever length i want, but before doing so, i just want to verify that this is okay. Obviously, i'd rather do my homework now than spend my money and find out later.

Since i've got your attention, is there anything such as a Toslink switchbox ? If so, does anybody know of one that works well and doesn't cost a fortune ? I would only need two inputs and one output.

Thanks for any and all help. When it comes to this stuff, i'm clueless : ) Sean
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sean
I consulted with our fiber optics guy, and as I suspected there are "switches": in fact there are multiplexers. The switch is implemented with a solid state variable opacity material, and is controlled by 0/+5 vdc. Just a guess but the cost would be about $100.

Why not just use a splitter?
This may be more than your Dad needs, but it could be something you or someone else need in the future. It will switch Video and audio source and has auto-detect and many more features. http://www.copperbox.com/lite/popinfo.php?lc_code=1154&PHPSESSID=fc9d8e777dfe68a0a1d201a6daffb662

Dave
I heard some unsubstantiated mumbo-jumbo once about Toslinks shorter than 0.5 meter being no good. This was audio shop water cooler banter basically.

From whom I heard this, and for what reason this is allegedly the case totally escapes me.
Sean - if you are doing Toslink, you should consider the glass cable from The Sound Prefessionals:
http://www.soundprofessionals.com/cgi-bin/gold/category.cgi?category=220&item=SP-TOC-99HQ&type=store

This one is almost as good as my best coax.
Sogood, I checked out your copperbox.com suggestion. this is good as I have been using a somewhat similiar Radio Shack Switcher, but I have been worried that it can't prioritize between signals. I like the fail-safe feature in copperbox.
El: Splitters end up in signal loss no matter what you do. I wanted to avoid that if at all possible.

Sogood: That appears to be a very handy device. I'll have to keep that one in mind for future reference. It looks like a very handy device to say the least.

Pm: Thanks for passing on what you've heard. While i have used a few different Toslinks, i don't know who or what to believe at this point.

Audioengr: I have two glass toslinks that are identical to these. Quite honestly, i don't know if i could tell a difference between these and a plastic DH Labs Toslink that someone lent me. Either way, neither DH nor these guys make a .5 meter cable. For some strange reason, i don't think that i could just cut these and re-terminate them myself : )

As such, can anybody state a case for / against "short" Toslinks ? C'mon folks, i know that we've got some technical geeks just sitting out there waiting to unleash their wisdom on the world : )

Honestly though, are Toslinks too "lo-fi" for us to discuss here ? I know that this is a question that seems more suited for Audio Review, but i'd rather not go there. Besides that, this is only for use movie soundtracks, so it's not like it will be used for "high quality" music. Now that you folks know this, it's safe to come out of the dark recesses you've been hiding in and speak up about your Toslink experiences and knowledge : ) Sean
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Sean...May I remind you that in the digital world a little signal loss, or distortion, is no big deal. The "ones", so long as the receiver can still recognize them, don't become 0.47's. Also, any "switch" is going to have loss. Two fiber terminations would be involved with inserting a switch. You might have more loss than a splitter.

A splitter is simple, cheap, and readily available. Why not try one, and then see if you can improve upon it by some other approach?
El: The splitter / switchbox is now a moot point. I just looked at the device that i was trying to hook up and it has four different digital inputs ( two coax, two optical ) that are switch selectable from the device itself. Can't ask for more than that.

Other than that, the reading that i did about optical splitters showed a VERY substantial loss in signal. Being the technical geek that i am, settling for something that i know will work but is known to be WAY less than optimum is not something that i like doing. Sean
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Sean..."There comes a time in every program to shoot the engineers and get on with the job".
FYI....The "typical" loss for a fiber optic termination/connection is on the order of 2dB. Two of them, so as to insert a switch means 4dB. When you factor in the loss of the switch itself you will end up near the 6dB to be expected from a splitter. (I assume that the splitter would be made with long legs so as to avoid need for extra terminations).