James,
Regarding the future monster BP-26 preamp, you mentioned a crossover would be an option. Might that include a sub option for those using main speakers (with passive crossovers) and sub(s)?
There is a dearth of really good electronic crossovers around, and it makes sense to incorporate one in a DAC/preamp.
My impression is, the 10B has not been updated to new circuitry.