XLR is one cable per two channels. You could conceivably run one toslink per two...

atoav · on Nov 26, 2023

Balanced XLR is three conductors per signal:

- Pin 1: Ground

- Pin 2: Signal in Phase

- Pin 3: Signal flipped

Two channels over XLR are done in two ways:

- digital using the AES standard and 110 Ohm cables

- analog using two balanced lines and a XLR-5 connector, although this is not an offical standard to avoid confusion with DMX

ender341341 · on Nov 25, 2023

I def could see doing that but don't think I've ever seen a system with multiple toslink for additional channels like I've seen done for XLR.