Has anybody had a play around with this? I know it's not deemed very proper for a stereo buff and I too have always wondered why manufacturers still put the extra speaker terminals on the back of their amps. However yesterday I decided to have a bit of a fiddle. So armed with a spare pair of Tannoy Mercury M2's I un-bi-wired my Castle Severns and ran them from my 8000sx. I then blu-tacked the M2's on top of my Severns (nice fit luckily!) and wired them to my 8000A. My first assessment was that 4 tweeters is bad! So I opened up the tannoys and disconnected the ones in here just leaving my Castles to do the delicate work. I couldn't really descern that one set of speakers was louder than the other which was my first worry (sensitivity mis-match). The M2's creating a bit of boom which is in their nature, but all in all I quite like the sound of it. It was quite hard to do back to back tests as 4 speakers has a lot more prescence than 2, even with 2 cranked up a little extra. It definetly had the kind of added grin factor you get when doing something funny and possibly quite silly with speakers. I'm going to keep it this way for a bit and assess how badly it's ruining my listening experience! So anybody else dabbled in this? Or done something else silly for the hell of it?