Docking optical connector

People asked awhile back if there was some way to get an optical output to be easily docked and undocked for use in a car environment. Would it not be possible to epoxy an optical cable to the sled in a similar fashion to what people do for the ethernet in home docking stations?

All one would need to do is drill a hole in the back of the sled in the spot approximately opposite the optical output on the back if the Empeg, run the cable through the hole, plug it in to the back of the Empeg in the optical jack, dock the Empeg, and epoxy the cable in place. To make it easy to dock and undock, the locking tabs could be removed from the cable.

Sound good? I think it would work fine. Something to try anyway.

Stu

People asked awhile back if there was some way to get an optical output to be easily docked and undocked for use in a car environment....
.... Something to try anyway.

I have just started to pay attention to the "digital out" thread -- finally got a receiver with digital inputs (and will likely buy one of your boards if still possible).

I wonder generally how desirable an optical interface would be in a docking environment. A docking connector would ideally have dust covers on both sides. How to make those automagically retract? Sockets typically have that but the fiber tip/plug itself? Even *with* a magical cover, I would think that frequent docking/undocking (esp in an automotive environment) would make this configuration more prone to dust collection and degradation. One other small question is how critical the air gap is on consumer fiber connectors -- if the fiber tip was not inserted 100% would you get signal attenuation?

Anyhow, if I do this, I think I'd be sticking with coax. Even then, I wonder about the rating (number of insertions) of typical RCA connectors as compared to the Empeg docking connector, but I figure it is worth doing. Easy to modify my home docking sled "plywood-n-ShoeGoo" adapter to incorporate a male RCA.

Cool stuff, man.

Yes, our sockets have an autoretracting dust cover. Cables or couplers do not. I don't know if dust would be a problem or not. I would suspect it would not be that big of an issue. The contact on the autoretracting dust cover during insertion might even serve to clean off accumulated dust.

I suppose that the intensity of the light would decrease according to the inverse square law, but I could be very wrong. I guess it depends on the angle of the light exiting the cable tip. I do know that the cable need not be inserted "100%" to produce sound. I have had it as far as 1/4" out and it still worked.

Regarding the life of the RCA connector. You could try what others have suggested doing. Run the coax signal over the mic in line. I am going to make a custom docking connector for my unit with a short female video cable connected to the mic in lines to avoid using the RCA connector completely.

Stu

I can pull my optical fibre connection from PC sound card to external amplifier out by 1-2cms and not have any degradation (noticeable to me) - it's as I'd expect with a digital system: all there or nothing there.

HTH,

A.

In reply to:

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it's as I'd expect with a digital system: all there or nothing there.

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I'm not quite sure it's as simple as "all there or nothing." As the limits of the optical receiver are approched, i.e. as distance increases and light reaching the receiver diminishes towards the minimum receivable signal and beyond, the likelihood of capturing every bit diminishes as well. You may get something, but it is not necessarily "everything." The more data loss, the greater the chance for audible distortion. AFAIK, there is no error correction in the optical component string. Also, distance most likely makes it more difficult to determine the proper beginning and end of each "0" and "1," giving rise to jitter problems and distortion. I'm sure some variation in distance is tolerated, but I don't think that going out 1-2cm would be a good idea to achieve best sound quality. Anyway, for the car dock, there is no reason I can think of why it can't be made to insert all the way in each and every time.

I was not able to get 1- 2 cm away, but it depends on the intensity of the light source as well as the sensitivity of the receiver end. A focused laser beam, properly modulated, would certainly do the trick.

Stu

I agree about jitter and possibly distortion, but it's not something I commonly do, and it's not noticeable when I do it! And as the gaps we're talking about are way more than would be seen in the empeg digital system, I doubt it'll be a problem.

Interestingly, it will keep an existing signal from further away than it will accept a new one - i.e. if I purposely break the beam with a piece of card or similar, it will not pick up again until I move the transmitter closer.

A.