[ScottMayo]

Anyone have any experience with RM/x on concrete vs wooden floors? In the room I'm building, I have a concrete slab, and current plans put carpet over that (and then a whole lot of treatments elsewhere in the room).

Adding a subfloor is a problem, because I'm trying to keep the room height at a certain size, and subfloors take inches. But if these speakers are going to suffer without a wooden surface to glue themselves to, I'll look at the trade offs. Or I'll consider some sort of "wooden box" platform just for the speakers. Any experience in this area, anyone?

(The room is (very roughly) 27.5' long by 25' by 11.5', if volume changes things. The RM/x will sometimes have bass help (probably from 60Hz or so down?) from a subwoofer.)

[Brian Cheney]

My soundroom is 31x14x9, a concrete slab with a rug over it.  Works very well with the RM/X.  I have the back of the speaker about 18" from the rear wall.

[cbartolomei]

My RM/X's sit in a 19W x 23L x 9H theater/sound-room in my basement.  They sit about 5' out from the wall and maybe 3.5- 4' from the sides.  I supplement them with a pair of Vandersteen 2WQ's.  And they sound great.

There's a thick pad and heavy berber carpet over the concrete.  I use moderate to minimal room treatment, but I do use a Tact.

Rooms can be mysterious.  This room had awesome deep and mid bass with my Genesis 200's.  

My Soundlab M-1's never worked in this room (to my ear).  No matter what amp.  No matter what sub- or how many!

In my room the RM/X's sounded best further out from the wall than Brian seems to place them.  It was a trade-off between deep bass and air/depth.  So, I supplemented them with the Vandersteens.  The 2WQ's ended up sounding best at the rear of the room.

[ted_b]

My HT is on a concrete slab, with carpeting.  It measures 15.25 ft by 22.92ft by 10 feet tall (at the center, 8 foot walls coffered to 10 feet).  My RM/X bases are 26.5 in from the front wall (which is covered in Sonex) and 23 in from the side walls, and they are dead straight on, no toe-in currently.  I've played with them in many many configurations (cross-fire, etc) and this works the best so far.  The bass is getting pretty well-defined (I also have ASC corner traps in the front corners).  I may add something like a pair of Room Lens (no longer being made, need to find them used I guess) to help with first reflections, cuz I can't dampen the side walls exactly where I want to.    On midrange-heavy recordings (Beck, Mutations, for example) the soundstage gets a bit cluttered.  Overall, I love the RM/X's and the concrete slab is not a deterrent.  

Ted_B

[Sedona Sky Sound]

My demo room has stained concrete floors. Totally a non-issue as long as you take care of the rest of the room with helmholtz resonators (to get the bass right), use a wool rug between you and the speakers (to reduce first order reflection from the floor), and tune the rest of your room with absorbers/diffusers to get the appropriate decay time for all other frequencies. I now have 3 recording studios that use my room for final mastering of CDs because my room/speakers are better than what they have.  

Julian
www.sedonaskysound.com