I am seriously ready to order up a pair of Axiom M60's, but I have a placement question. The front speakers will have to sit to the side of an entertainment center, and on one side there is limited space between the entertainment unit and the side wall (18").
The M60 is 9.25" wide, so that leaves less than 9" of space. Is that enough? What is the rule of thumb for open space to the side of the speaker?

A general rule is to give vented speakers as much space as possible. Maybe someone who has his/her speakers set-up in a similar fashion will chime in. Constrained spaces tend to make the bass a little boomy.

I wouldn't worry about the space, you make do with what you have and The benefit of the floorstander over a smaller speaker is worth the minor reflections you may have off the wall. I have an M80 closer than that to a sidewall and they sound great.

I also have limited space on one side for my M80s and haven‘t noticed any problems. When calibrating them I just had to bump up the opposite speaker by 1dB to get the SPLs to match.

If you can keep the driver cones of that speaker from being equal distance from both the side and back walls you should be able to avoid the boomyness St_PatGuy mentioned.

@ St_PatGuy - Happy Moved Saint Patrick’s Day!

Woo hoo! Thanks!

Oh, it's that time already? Happy Birthday, Sean. I hope things have improved since you were born in that puddle of green vomit.

Monday is the big day. No more puddles of green vomit for me. Instead, I try to ingest as much green food coloring as I can so my pee is green. Wait, wouldn't I have to use blue food coloring for that?

http://www.catholicnewsagency.com/new.php?n=9917

Guess that means we get to celebrate twice this year since the secular celebrations didn‘t change. Bonus!

The m60's should work very well, when I had my old m60's upstairs it was in a similar situation..

Those Irish Catholics have their priorities straight, I see.

< Irish accent >
What's that you're sayin' Seamus? St. Patty's Day falls on the Monday of Holy Week? Jesus, Mary, and Joseph! But that means.... That's it! We'll call the bishop!