I only just got the D1+ from another head-fier and am curious about some of the mods. I've already adjusted the volume control for the pre out (I am also using this with the Magni). Now I'm interested in trying out the OPA627 opamps. As I was looking into this mod, I came across some info on a Class A biasing mod that people have been doing on the Matrix M-Stage. This is not my area of expertise at all, so forgive me if the answer is as obvious as my nose: would the class A mod would work on the D1+ too? It is possible to buy the OPA627s with the biasing mod already done, btw.