Not quite sure but, if my movie room is 14 x 21 x 8 for movies alone.
If I am using say M22 and two subs' say EP500's what would my benefit be in having M80's and two EP500's, if there is.

Now for upstairs ,music system if I have M80's, would the EP 400's be a good choice. One beside each M80. I really don't care for subs with music, but these 400's seem like it would be a good match. Just that little extra umph in the lower end.

I have MK 750's now and love them like no other, but they as any bookshelf need a couple subs. That is a given specially since they are only designed to go down to 80hz. which is not an issue since that's where most crossovers in my pre/pro kick in.

M22 and dual EP500s would be virtually identical as M80/EP500 for movies, you might get more 'feel' from the mid/upper bass from the M80s same goes for music. The EP400 plays low enough but lacks enough SPL to make much difference with the M80s playing, at least with my experience I had with a single EP400 and M80s dual 400s might work better.

Thanks
Just curious about this. Some say bookshelfs and subs are just as good, specially since it is the Centre Channel that carries most of the action.
I am trying to figure out where the benifit would be. Given that my cross over would be set for 80 hz, and the subs to each side. I just think, if I have M80's and a EP 500 next to each just how much bottom end am I really hearing from the M80's, "IF" the sub is producing the 80hz and below. Am I hearing any or much 80 -25 hz from the M80's, specially if the EP500 is doing it's job.
Really how much difference would I hear noticibly, if I had two great bookshelfs and two EP500's or the M80's and two EP500.
Also, if the Bookshelfs only need to go to 80hz and the sub say 100hz and below ...would this not be benificial for my AMP not to have to push extra wattage. Whereas, if I had M80's the amp would be pushing wattage to the 80's for lower frequencies. Why, double up on the 80 - 25 hz with two M80's and two EP500. If calibrated properly and they blend in right wouldn't having a great bookshelf and a great sub together be like a great floorstanding speaker ?
Actually, I think it would be better, has too be .... I have a bookshlef capable of handling 200w and I have a EP500. I would get awesome clean power from the amp ... never have a need to worry about the lower current drawing frequencies. I have a very capable sub giving me loads of clear bottom end. My amp Denon 3805 with two external Emotiva UPA1's plenty of juice for the bookshelves should be very clean.

I have M22's and EP500 and love my setup. However one advantage to me is that with M80's you have an option for a lower X-over point (say 40 or 60Hz) which means the subs will be producing even less 'directional' content than if the Xover was higher (like 80 or 100Hz). That could make a for a very well blended system with the subs being able to better 'sonically disappear'. Of course we are starting to talk subtleties here,this is not necessarily night and day differences. Also keep in mind that the M80's are very well liked for their midrange and top end. However you are also right in that M80's will be more taxing on your amp, but if you've got the wattage that's a non-issue.

Yes, that makes sense on the X-over point. But, wonder how much of a difference will the "directional" notice be between an 80x-over and 60 x-over. Kind of like, if I could A/B Switch the 60/80 Hz on a sub, to see how much is noticeable. When playing movies.
I currently have MK 750's and the detail, clarity and imaging is un-believable with them. I have no sub .."Yet" and am trying to justify not having to buy, two pairs of M80’s..... One set is a defiantly for the music upstairs in the living room.

But, if needed I will sell them and put the money towards the M80's and VP180 in the future.

I am amazed right now, I haven't calibrated yet but, even in Stereo, I can hear phones and bugs and extra sounds coming from the back corners of my room. Even though say a phone is ringing in the background of a movie I am watching. I will hear that phone ring in the rear of my room in the left corner. Weird it just appears there. Shouldn't the sound come from the left front speaker? I don't hear it up front at all. I guess, really the only way to find out is get a set of M80's ...going to anyways and A/B the two and find out

Thanks for your input

For downstairs, I would say there is no benefit to having M80's if you are using it only for movies and crossing it over at 80 Hz as you would not be utilizing any of the lower end capabilies. An M22 should give you the same effect.