Take a casual look at the Mk.II edition of MBL's Reference 101E Radialstrahler loudspeaker, and you won't immediately see what's new compared with the original version, which I reviewed in October 2004. But the Mk.II has a shorter, sleeker bass cabinet, designed to, among other things, slightly lower the stack of omnidirectional drivers it supports. While the many other major revisions to this familiar and fascinating loudspeaker can't be seen, it's fair to say that, from the ground up, the Reference 101E Mk.II is a new loudspeaker in design, if not in concept.