FYI on a new DAC I have hooked up with my VM-1a and SR1a (have not tried the CA-1a with it yet).
The best DAC I have had on the VM-1a was the Lumin X1 followed by the Benchmark DAC3B. DACs that were warm or smooth, such as the Musetec 005, did not work for me with the VM-1a. Though the Musetec 005 was great on my 2-channel system. I used the built-in fibre streaming for the X1 and Sonore OpticalRendu for the DAC3B. I also used the X1 as a streamer for the DAC3B.
Last week, I bought the Schiitt
Yggdrasil+ and paired it with my fibre optical streamer (Sonore OpticalRendu). I got the Less Is More version of the Yggi. This is the WORST measuring of the 3 Yggi options. This DAC sounded a lot like the $15K Lumin X1 (now sold). In fact, it is even better on the VM-1a than both the DAC3B and X1, which makes it the very best DAC I have heard on the VM-1a.
It is not rounded off on the top as the X1 nor as bright as the DAC3B. The fact that it does all of this at $2300 makes it a great buy in my books.