Torpedo Live s/pdif output to iMac query

I'm wondering how I use the spdif digital out on the Live with my setup: -

I have an original Apogee Duet FW going into a 2013 iMac (via Thunderbolt) and running Logic Pro - the duet has no spdif input so is there a way to connect the Live's spdif output direct to the iMac's optical input?

I presume I would need an spdif audio to optical converter?

your session will need to be at 48kHz or 96kHz ie not 44.1kHz

you'd also need, as noted, a coax to optical converter and

you'd need to set up a aggregate device (combining the duet and the internal input) This is done in setup, AudioMidi

Andy