diy Optical SPDIF Switch?

[audiogeekess]

input: 4 x optical SPDIF
output: 1 x optical SPDIF

What should I buy? Or should I just buy that one for $60 of amazon--premade?

I'd like to integrate it into a DIY preamp though--so leaning towards diy.

Thanks.

[UV101]

Why do you need optical out?

It would be difficult to switch light. I'd imagine the commercial ones convert to spdif to switch and back to tos to output. The actual tos receiver (connector) will output spdif on 2 of it pins. You could use relays to select which input you require.

[audiogeekess]

I need optical out because i have it feed into a dac that has an optical input. Well it also has a coaxial input (you can toggle switch it).

[linuxworks]

4051 style cmos switch or TTL version of 8in 1out mux chip.

its what I use for my spdif switch

either one works; I tried the analog switch and the ttl switch and both work fine for spdif speeds.

make sure you get 5v toslink blocks and not 3v ones! they make 2 kinds so be sure.

(my spdif switch is controlled by i2c and remoted from another preamp. if you are not in a hurry, you can wait for a board run for my project).

[jitter]

Originally Posted by audiogeekess

input: 4 x optical SPDIF
output: 1 x optical SPDIF

What should I buy? Or should I just buy that one for $60 of amazon--premade?

I'd like to integrate it into a DIY preamp though--so leaning towards diy.

Thanks.

DIY? Well then, here's the thread when I built mine: DIY DAC with input switchingon a budget?. Somewhere in it, you'll find a link to a website with the design that was the inspiration for my own concoction, skip to post #37 of that thread. I use it every day and it works fine.

I made one with two coax in, two optical in, one optical and one coaxial out.
Should be easy to modify to your needs, though...

[UV101]

I'd be interested in a comparison between a digitally switched version and a mechanically switched one. I tend to lean towards the latter option eliminating on chip crosstalk. I accept that using mechanical switches has it's own issues, but I like the idea of the complete isolation.

[jitter]

Wouldn't there also be crosstalk in a switch?

[UV101]

Originally Posted by jitter

Wouldn't there also be crosstalk in a switch?

I don't think running independent relays to switch 4 inputs to a single output would suffer from crosstalk. Each input would be completely mechanically isolated from each other. As stated there are other considerations such as contact resistance, size and more complex switching to control the relays. I'd still chose this option over a single chip acting as a switch with all signals present on die at all times.

[Mooly]

Optical SPDIF doesn't always behave as you might think,
Optical splitter... used as a combiner :)

3 way switches,
Optical splitter... used as a combiner :)

PRO SIGNAL|PSG00950|3-WAY OPTICAL SELECTOR SWITCH | CPC Products&MER=e-bb45-00001001

[UV101]

Originally Posted by Mooly

Optical SPDIF doesn't always behave as you might think,
Optical splitter... used as a combiner :)

3 way switches,
Optical splitter... used as a combiner :)

PRO SIGNAL|PSG00950|3-WAY OPTICAL SELECTOR SWITCH | CPC Products&MER=e-bb45-00001001

I'm guessing those are using a prism to reflect the light much the same way that a projector will combine the separate Red, Green and Blue displays into a single image. Not convinced a cheap plastic prism is the best way to go

What about something like this?

DIY input selector

You only need to use 1 of the channels for the SPDIF. Any TOS receiver on the input will work.