Speaker placement on a Brick Floor?

[Quickley17]

I have a fireplace in my walk-out basement which has, for lack of a better term, a brick "mantle-floor" that extends about two feet into the room, and extends to the walls on either side of the fireplace. The total length on each side of the fireplace is about 6 feet, and I want to put speakers there.

Does anyone know about the resonant/vibrational properties of brick, and whether it is a good idea to place speakers on a brick surface or not? In my head I have come to the conclusion that brick transfers vibrations pretty easily which is why you cant use it to build in places like San Francisco and Los Angeles, and that this might be detrimental to the sound of speakers if I put them on a brick surface... Is this off base?

 

[Quickley17]

Well I tried it. The results were sub-par. My sample of one indicates that I should not put speakers on the brick front of my fireplace in my basement.

 

[GO-NAD!]

Well I tried it. The results were sub-par. My sample of one indicates that I should not put speakers on the brick front of my fireplace in my basement.

Did you try bringing them out onto the floor and compare with the placement on the bricks? I would think that a brick floor would be much less resonant than a wooden floor.

One other thing to consider - placing them on the brick is bringing them closer to the wall behind as well. This could result in exagerrated bass response. That may be what you are hearing?

 

[Quickley17]

I did. The floor in front is carpet over concrete, and the sound improved drastically. The room is not optimal for sound, I think due to alcoves and an open frame staircase at the rear of the room. With the speakers on the brick, the bass was exagerated, but not nicely. It was almost like I was hearing it twice and it was extremely distracting and sounded like garbage. Is that what you are talking about? Even the high frequencies though sounded strange. They were harsh, and almost had a ringyness to them that seemed to be coming from all directions. There was no imaging whatsoever.

These issues mostly went away when I moved them forward onto the carpet.

 

[GO-NAD!]

I did. The floor in front is carpet over concrete, and the sound improved drastically.

Well, I guess you should leave them on the carpet!

With the speakers on the brick, the bass was exagerated, but not nicely. It was almost like I was hearing it twice and it was extremely distracting and sounded like garbage. Is that what you are talking about?

Er, I guess so. I'm no acoustics expert, so don't take this as gospel. My guess is that the brick would be more reflective than drywall and may make standing waves worse. I'd wait for somebody with more knowledge in this area to comment before accepting that opinion though.

Even the high frequencies though sounded strange. They were harsh, and almost had a ringyness to them that seemed to be coming from all directions. There was no imaging whatsoever.

That's really strange. I got nothin'....