I am very familiar with this speaker. When I was in college, many of my buddies wanted reasonably priced speakers that could emulate a "high end" sound system, but of course, could not afford the price of entry into true "high end". This led me on a quest to find them a resonably priced speaker around $500.00 that could actually image on cheap electronics no less! Enter the DCM Timeframe. This speaker will present a very strong center image and a good image spread from just a japanese receiver, from that era!
They have decent dynamic capabilities other than their low bass and can be played above 100 dB. One of their design compromises is having the ability to play true deep bass as they are a quasi transmission line two way using drivers from that era that didn't have the xmax or magnetics of today's drivers. The bass is very tight though and that made them special too. Regardless, they were truly a special speaker helping many a friend transition into high end audio due to their imaging capabilities. If you decide to tear into them I would start by trying different wiring and better crossover components (of the same values mind you). The people who designed these speakers realized they wouldn't be powered by high end electronics so their voicing may be compromised if you monkey with them changing drivers and such