Go for it, Wolf! A friend of mine used to run tri-amped - a single 18 of unknown provenance with an SVT 8X10 cab modified to replace the middle 4 10s with a 15. Ashley preamp & Furman x-over (or maybe the other way - it's been almost 30 years); Yamaha (forget the model - whatever was 2X250 back then) for 18 & 15, power section of an Accoustic 360 for the 10s. It was amazing. He had been running 2 SVT 8X10 cabs, & was blown away by the difference big speakers made (...8 woofers - that phrase only makes sense to me if you put a 1 in front of it )
Peter