by Y-my-R » Wed Feb 07, 2024 2:15 am
I have ever only used digital patchbays to "mult" optical signals. But these kinds of patchbays connect to their own power source, so there's no loss in signal strength when the signal gets duplicated.
I did that back in 1998 or so, with a Digidesign ADAT interface and an old Blackface ADAT, but routed the I/O from both, the ADAT interface and the ADAT to a Fostex DP8 digital patchbay, and sent the same source signals to a Yamaha 01v mixer, in addition to between the ADAT interface and the ADAT. The ADAT Interface/ADAT needed to have a "closed loop" and an extra 9-pin D-Sub sync cable connected, in order to make the sync work (and I did the Timecode sync via a Motu MIDI Timepiece AV, back then).
But by "duplicating" the signal coming out of the ADAT and the ADAT interface, and sending it back where that signal was needed, but ALSO sending it to that 01v mixer, it all worked perfectly, together. I could still even pull ADAT tape backups of the tracks running in the computer with that setup.
Now I'm having the ADAT I/O from my Apollo 8, my PreSonus Quantum, and two Tape I/O cards on the D8B (DIO8), as well as the Alt I/O (OPT8) on the D8B, go to an M-Audio Digipatch digital patchbay. A third optical cable pair is connected directly between the Quantum and the 3rd Tape I/O card (DIO8) - not enough optical I/O on that patchbay to add that (that's why I'm still looking for a Frontier Design Apache patchbay, since that one has 12 optical pairs). Oh, and there's also an M-Audio Octane connected to the digital patchbay, that I mostly used for it's line-input to A/D converters, to feed analog signals back into the Alt I/O's ADAT input as an FX return.
All of this works flawlessly (...everything runs off of the same word clock... and a few more digital devices. Nowadays, I only use the digital patchbay for ADAT, and made S/PDIF patchbay out of an old SDI BNC panel... to maintain the 75 Ohms needed, that wouldn't be there if using an RCA patchbay).
Anyway... my point is, if the splitter has it's own power supply, there should be no signal loss.
What I DID read before, but haven't tried myself is, that "glass fiber" cables are superior to plastic based optical/TOSlink cables. Supposedly, there's less jitter happening over the glass-fiber based cables.
Personally, since I'm always strapped for cash, I've always been using cheap plastic-core optical cables. Works fine from what I can tell, but who knows... there might be an improvement in imaging or the stereo field, etc. if there's less jitter happening. But at least I don't consciously "hear" that there'd be jitter in my setup (but there ALWAYS is... just depends on if it's so much that it impacts the overall quality).
So, I'd just get a splitter that has its own power supply, and then you should be fine.