I've been looking for a simple solution to control vibration when people are walking on the floor above my projector (PT-AX100U).

My drop ceiling is already in so it would be a real pain (unless someone has a simple solution to do so) to run a new stud that sits on the concrete foundation separate from the framing of the floor above.

I already have my projector mounted with a telescoping mount from Visual Apex (AV-813U).

I came across this solution and I was wondering if it would work and if any of you have tried it:

http://www.acousticalsurfaces.com/rsic_clips/risc_dco4_electrical_box.htm?d=46

Use expansion shield cement anchors and screw the mount directly to the cement instead of the studs.
All you need is a drill and a 3/4 inch cement bit , it takes 5 minutes.

As I said, my drop ceiling is already up and I don't think it would be too easy to get a 14' beam up there to screw into the concrete. I was hoping to use the above solution to mount a stud between the floor joists with the sound isolator clips. Has anybody tried this?

As I said, my drop ceiling is already up and I don't think it would be too easy to get a 14' beam up there to screw into the concrete. I was hoping to use the above solution to mount a stud between the floor joists with the sound isolator clips. Has anybody tried this?
The product you are looking at is used to isolate sound vibration which is different than the actual flexing of the floor/subfloor/floor joists to which your PJ ceiling mount is attached to. you either need to significantly stiffen the floor system above or separate the PJ mount from the floor system. I thought I read a thread earlier this year where someone also had to do this but i can't remember who or when it was. Good Luck!

Thanks that makes sense and my job harder. Anyone out there know a simple way of getting a 14' beam up in an existing drop ceiling without tearing it apart:-)

What would it take to stiffen the floor?

My ceiling /floor flexes too. My solution - have everyone in the house downstairs watching the movie then no one will be upstairs making the floor move.

I bet everyone has this same problem as there is no simple fix.

I know but it's really annoying me during football sunday's! I have to find a solution. I was thinking of cutting up a beam in irder to get up above the drop ceiling and then screwing it back together up there.

rastan- How far from the back wall is your pj mounted? Reason I ask is that maybe you could mount a shelf to your rear wall and place the pj there rather than rip down your ceiling to mount a stud to hang it from. That route would seem to me to be much easier than attempting to cut and reaasemble a stud in your drop ceiling.

Unfortunately the back wall is another 15 feet back from the projector.

rastan try using unistrut it is steel it is only 1.5 x1.5 inches square you could go from wall to wall with a few connectors. comes in ten foot sticks it would give you a ridged mount with the least amount work

Interesting. I've been living with it although I cringe everytime the kids jump in the room above the projector. Where do you get this unistrut? Your saying I can buy 2, cut them to length and it would be rigid enough to support the projector over a 14' spread?