Vibrating floors are a two-way street, eating certain enery and pumping back/increasing other energy, if only as the "in the shadow" effect.  I would not bother to try to math/model it when emperical testing will tell me anything I want to know about it.  But it certainly warrants investigation, and I would be surprised to learn that you are unable to discern differences in the floor tension, once you are operating FR.  If you are still unable to tell a difference, there may be some other issues to attend to prior to attacking the floor.

Generally, one places jacks under beams that run perpendicular to floor joists, for a +/- "whole floor" strengthening aproach.  However, Jessie is correct in saying that a jack can also act as a ground path, so placing them under a given spot can have a particular effect.

Romy, if you ever said whether the joists below your listening room are already insulated and/or sheetrocked/plastered, then I forget.  However, you might want to re-visit what has already been submitted on this, since there are some good ideas there, already.

Getting the floor tight is basically just another way of getting control over one more variable; and who wants more variables in the quest for decent LF?   Tightening/grounding the floors should make it easier to set up and dial in your LF.  And unless your new house is freakishly overbuilt, it will also ensure that your 1,500 pounds of equipment do not permanently deflect your listening room floor joists, causing poor little Koshka to roll down into the new trough when she falls asleep listening to music.

The only case I could imagine where a grounded floor would not not outperform a pumping floor is....  OK, I can't think of a legitimate case, but I could imagine a case where spurious gain at some room resonance mode was somehow found to be "desirable" in augmenting a particular system deficiency.  However, I might as well add here that I do not hold the view that one way is as good as another to damp peaks and fill in troughs for a flat chart.

Generally, I think it is good to trim back from too much energy.  What a nice "problem" to have!  Still, I generally don't like, and I generally avoid, weird peaks.


Best regards,
Paul S

I thought the closer you got to the corners of the room the more floor support you would have in a given room, with sub flooring, your floor joists are going into blocks on the edge of your house so that would be the most support for Macondos, weight. But you want to go away from walls, closer to the center of room, with less support for better presentation. I like the idea of one more bass module for each side. Do you mean twin towers on each side?   I had hoped that in the future you would build large horns for the bottom end of your system, since you have your own place and more room.  We are all looking forward to future projects when you have the time. 

KLegind wrote:

I second that. Please tell us about the design decisions and topologies that made this presentation possible. I guess it has very much to do with room and placement in room.

jessie.dazzle wrote:

Assuming situation 2 is possible, receiving mid-bass primarily as reflected sound, one would have to take into account the reflected path of that sound, and how it describes the mid-bass part of the image, relative to the MF/HF part of the image; for example, the reflected mid-bass may very well originate on the left, but reach the listener's ear from the right.