Originally Posted by stevegamble66
Sounds good.. I had to read that twice.. but I got it.
Now if I were to switch my fronts to small and use pre out R / L receiver XO @160hz.
Would that give me the same thing?
Or ,the receiver would pass the the <160hz ALL to the LFE ?
None to pre out R/L.
If you set the receiver XO to 160Hz, you will need the MBMs hooked to the LFE out. Otherwise, if you have them hooked to the mains, they will only get bass down to 160Hz since they would be part of the chain for the main speakers.
If you have the MBMs as part of the LFE chain, then you are good to raise the XO in the receiver up to 150~200Hz (make sure the MBMs are up front, close to the speakers, the higher you go). If the MBMs are hooked to the main speakers, then the receiver XO should be 50Hz or wherever you want to crossover between the MBM and the main sub.
But if you hook the MBMs to the mains, don't use the analog pre-outs, for the reason I mentioned - if you do use the pre-outs, you'll have the speakers playing that same bass as the MBMs, which could possibly cause cancellation and phase effects. You want the MBMs to be the only ones playing that range.
As to your other question, about which would sound better... There are trade-offs.
If you have an MBM hooked to the left/right mains, then you can get added benefit of the stereo / directional bass. There's often bass sent to the main channels, not just LFE. So you could get more of the effect of it coming from the speaker it was intended to come from.
On the other hand, having the MBMs hooked to the mains means that the MBMs don't play any of the 50Hz+ bass present in the LFE track (which can go up to 120Hz). So in this case the main sub would be playing 50Hz and below from the signal re-routed from the rest of the speakers, plus the full LFE signal (don't engage the main sub's internal XO in this setup case, because you'll filter out this LFE-only bass above 50Hz).
Hope that makes sense.