Wasn’t very clear in my statement - I have a Topping D90 DAC connected at SHD coax digital to use instead of SHD’s DAC for my speakers and use SHD’s DAC for the subs.
I use an external DAC with SHD for a silly reason - it measures a bit better, has audibly less noise although irrelevant at listening distance. Many claim D90 sounds good while it sounds the same to me in proper volume-matched A/B comparison. I might replace SHD with the all digital Studio version eventually and will need the external DAC then.