Thanks wayne... we won't be pushing them that hard anyway. It's a recording studio and the room has a nice neutral sound... so it' merely for extending the LF for our monitors (Genelec)
I'm going to be adding a pair of TwoPi bookshelf to the control room soon and wonder what the best way to tackle switching the frequency point on the subs would be. switching between a set of powered Genelec monitors NS-10s and the Two Pis. The NS-10s and TwoPis will be run on a Dynaco ST-70 and we have a Hafler P3000 to run the subs.