Toslink

75-Ohm SPDF and USB traditionally considered to be better type of connection for audio, however comparison is kind a not fair due to lack of high quality Toslink cables on the market. In situations where you have to use interconnect longer then 5ft Toslink could be optimal and superior over other. If you have to use Tosliink, the Borosilicate Glass fiber cable is way better than plastic fiber. 

@mdrone

Apologies - I missed that in your reply.

It looks like the Toslink and SPDIF inputs on the Madison are equivalent in terms of technical capability. I don’t see a way for you to connect the Bricasti M5 to the Madison via Toslink though. The webpage only shows USB and AES / coax SPDIF digital outs.

If you’re averse to using Toslink still, there’s the option of putting in a SPDIF switcher so you can choose between the streamer and the CD player.

Otherwise, I suppose your DAC search continues.

No worries Yage.

You are correct vis a vis the M5.  If I went with the Wattson I would also need to buy another streamer ( with a Toslink output).

thanks for diligence’

No problem.

Here’s a switcher I found on B&H ($119). Looks like it’s from a company in Oregon that specializes in making gear for the broadcast market.

https://www.bhphotovideo.com/c/product/1351618-REG/inday_da4x_r_spdif_4x1_digital_audio.html/overview

Just something to consider.

Slow Toslink transitions convert system electrical noise (on both ends) to jitter (but Toslink is immune to ambient electrical noise and doesn’t create ground loops).

Fast coax transition produce reflections on characteristic impedance boundaries, that convert to jitter (deform original edge).

I use Toslink with Benchmark DAC3 (good jitter suppression).

There are some many variables - you have to try both in your system and in your room. Same goes for coax cables - the most expensive one, recommended by others can have poor impedance matching in your system, while the cheap one can be perfect. Pay attention to overall sound clarity since jitter converts to added noise.

USB should be the best, since it cannot directly induce jitter (being completely asynchronous), but can inject electrical noise to DAC affecting D/A conversion timing (indirect jitter).