is the bass better with 2 bass drivers. bein 40cm deep it gives you more bass anyway.i have the OB1`S had the from 2003 and still sound great. but i dont like the bass drivers to much. not much flex in them. had to buy 2 new bass drivers i blow the last 1s by bridgin my nad amps at 300w.dont think the pmc`s drivers like takin a lot of power