I recently installed a pair of B Tech, BT-77 wall mounts on my RTi38's. Here they are:
My first listening position was on top of the entertainment center, L & R obviously. The speakers sounded real good, as expected, but since the entertainment center is from IKEA, it vibrated enough that my bat like ears heard it. Overall performance of the speaker was average. Midrange was a little muddy, bass was boomy.
I installed these brackets and my result was clearer midrange and above average treble, not bright. The treble I expected to not be amazing anyhow, its not an LSi, but it stayed just right for me. Problem was that even though it improved my stage and imaging from listening position, was that I lost alot of bass presence, ALOT. What was present sounded "hollow". My theory was that I was getting too much resonance from the mounting surface, and it was "eating" my sound.
12" from side wall
6" from rear wall
70" from floor to bottom of speaker
8" from ceiling
Speakers are approx. 7' apart
8 degree downtilt
2-3 degree inside angle
The speaker position is quite nice and causes my front stage to achieve an "arc" in a way. The arc being, that instead of a flat stage, my front speakers are a little more forward of my center channel. The space between the speakers isn't too large, and it fills perfectly from the listening position
The dimensions are not very changeable. Factors in mounting included stud placement and entertainment center.
Anways, back to the bass issue. I recalled reading about using Vibrapods or a similar damping materiel, to help with resonance and/or sound problems. I had a limited amount of options available to me since they were wall mounts. I had some previous experience with Dynamat, www.dynamat.com , so it seemed only logical that the same application for car stereo speakers, would be a viable option here.
I purchased a 2-pc. pack of 10" x 10" Dynamat Extreme for $20.00 at BB. They have two lines, the original Dynamat is a little thicker(1.70), the extreme is thinner(1.44) and lined with aluminum. BB only had the Extreme version, FYI. I won't get into the specifics aside from I wanted a thinner format, tho' I don't prefer the aluminum "skin". I didn't want to chance adding a somewhat permanent item to my mount and it be too thick and mess the whole project up. Things went well tho' and the thicker format would have been fine. For specifics on Dynamat, please check out the website.
I broke the mount down into the four main pieces: Back plate(Wall plate), the speaker base and two adjustable side arms. I cut the pieces to fit all the respective parts. I had some extra small pieces, so I stuck them to the front of the back plate, in addition to covering the entire rear portion. Re-Assembled kit and mounted to wall again.
Dynamat Applied: http://home.hpphoto.com/servlet/Link...cf348e&size=lg
Back plate Mounted: http://home.hpphoto.com/servlet/Link...7218e4&size=lg
Complete Mount Installed: http://home.hpphoto.com/servlet/Link...3218d0&size=lg
The treble stayed about the same, no worse for sure. Midrange warmed up very nicely, some tested artists were Days of the New, Michelle Branch and Alice in Chains - Unplugged. All are strong for midrange and vocal listening, IMO. I found the music to overall have a nice strong warm feeling. Travis Meeks(DOTN) voice was solid, the acoustic guitars were precise. Michelle Branch also sounded clear and as cute as ever. The acoustic guitar work from Jerry Cantrell and his asscociate, was tight and dead on "live" sounding. It helps that it is a nice recording, but the music improved to me.
Houston, we have BASS! Well here's the thing, yes I did get back some of my bass presence, no more hollow sound. Upper bass levels were punchy, but I believe that I still lose whatever sub-sonic/ lower bass levels were even available in the first place. This is caused by room factors and the less than ideal construction of my mounting wall.
But am I pleased with the results? Of course. It was a $20.00 investment that improved my sound enough that it was noticeable. I achieved the effect that I wanted, improved bass, from a no bass starting point. Mission complete.
Sorry that this is so long but I felt it was informative enough that someone may find it useful. Forgive the lighting in a couple of the pictures, I had to use no flash due to that damn aluminum. :)