The main difference is the way it presents mid-bass. More punch and detail in G91 then Sonos. But again, it's hard to hear any difference at all in a direct comparison. To most people - even most high end buffs - this discussion will be highly theoretical. Which again raises the question of the sense in producing megadollar transports/players today. Will we see a 808.4?

Current M-related equipment: DSP7000 (2), G91A FM, Sonos ZP90/ZP80 Zone Players, F80 (kitchen,yellow).