I merely have the RS 2.5s but recently added an active crossover - a Rane AC23 with 4th order filters. Just has RCA connectors so relative phase inversion was not a risk - one can always swap speaker cable landings.
It was already bi-amped with a MC2105 at 105 wpc for the top and a Sony TA-N80ES at 270 wpc @ 4ohms on the bottom. The McIntosh is not exactly a tube sound but with autoformers it will have to do.
I didn't find setup complex or difficult at all. Flipped the "bi-amp" toggle, set the crossover point at 300 Hertz and fired her up. Did a little tweaking on the channel gains for high and low and played with the treble gain plugs but that was all.
The result was a much clearer and better defined bass note. The downside was a touch more edginess from the op amps in the Rane. The signal goes through half a dozen op-amps before the output to the power amps and one can hear it. On the whole, a net positive but it might not turn out so on a different speaker.
Might still recap the existing crossovers since separating the EMITs and the EMIMs seems to require cutting wires. Likewise the Watkins woofer. There is a crossover just on the bass to drive separately the 4 ohm and 2 ohm coils.
All in all, going active was not much trouble at all - $50 for the Rane and $50 for the extra interconnect cables. My advice is to stop worrying and try it out.
Of course, I only paid $128 for the beasts in the first place! Add $50 for new woofer surrounds, $10 for two bottles of lemon oil and steelwool, $60 for two pairs of speaker cables (home-made!) and then the active crossover, I'm in it for about $350. I would have a tough time getting equal sound quality at twice the price.
