I would say that the XDS1's bass is significantly tighter than prior EMM Labs efforts, at least compared with my CDSD SE/DCC2SE units that I used previously. It also gets a good deal more of the low level detail, IMO. The use of the Esoteric transport mechanism in the XDS1 is a big plus, and a major reason I got the unit. I will note that the output level of the XDS1 seems lower than the DCC2's output--I have to turn up the volume to get the same levels I used to get. Don't know how it compares with the one-box CDSA.
My recollection of the Accuphase combo, going back a while, is that it was wonderful to listen to but perhaps a little on the warm side, so not sure how that will work with your room's bass issues. I haven't heard the latest DCS, so can't comment on it or the ARC unit. I would say that if you like the EMM Labs house sound, the XDS1 is an excellent choice.
My recollection of the Accuphase combo, going back a while, is that it was wonderful to listen to but perhaps a little on the warm side, so not sure how that will work with your room's bass issues. I haven't heard the latest DCS, so can't comment on it or the ARC unit. I would say that if you like the EMM Labs house sound, the XDS1 is an excellent choice.