Thanks for the hint to search previous threads for cross over info - interesting stuff.
I'm pretty sure that when no sub is configured, the .1 info is sent to the fronts if set to large. At least, the rattling windows would suggest that is the case
I could be wrong though. I'm not sure if the .1 is also sent to the centre if set to large as well (anyone know ?)
It's an interesting comment about the cross over also being applied to the sub and on one hand makes sense, but also doesn't. It's an easy decision to route any bass information for any speaker that can't handle it (ie small) to the sub but not such an easy decision as to where to route higher frequency bass in the .1 channel when the sub can't hajndle it. It would make sense to send this to the fronts.
I may end up getting a sub at some stage but right now funds declare it has to wait. The problem is getting a sub which can deliver bass as cleanly as the IB1's (up to the point where they run out of steam).
I haven't yet done a good test on the CB6 - my initial impression though is that it sounds a little "boxy". However, this is based on about 10 miuntes of listening, it's not properly positioned, not run-in or calibrated for volume or delay and so I'd take this with a pinch of salt.