Subwoofer bouncing on floor

[Zorba]

I have an old style Elemental Designs A3-300 down-firing subwoofer. When I first bought the subwoofer it was on a wood subfloor. I have now moved into a house with a concrete slab floor. I have noticed that the subwoofer will now sometimes bounce in place, when I have music turned up (~85-90 dB). The spiked feet will then hit the concrete an make an awful rattling sound, much like a license plate on a car with a system. The sub sits on top of medium thickness carpet, which is on a high quality pad. If I put some of my body weight on the sub, it will stop bouncing. I was wondering if you all had any recommendations on how to fix this problem, besides stacking free weights on the sub.

BTW: This sub weighs in at 100 pounds, so I would think it'd have enough weight to hold itself down, guess not.

 

[SithSolo1]

SubDude or Gramma or Great Gramma Depending on size of sub

You can probably use the spikes with that or someone suggested you can take the spikes off and use hockey pucks(or anything) to keep the the driver off the top of the mat.

 

[sdifox]

put some books on it.

 

[Howard]

Newton pwns you.

 

[Rifter]

A buddy had this problem also and we put a piece of 1" MDF cut/painted to the size/color of the sub ontop of it. problem solved.

 

[amdhunter]

100lbs and still jumping? Damn!
How about rubber under the spikes to dampen the sound a bit?

 

[goobernoodles]

eD makes sub isolation mats. Buy one. Check the dimensions since they have since changed the A3-300 to front firing.

http://www.edesignaudio.com/product_info.php?cPath=2_126&products_id=949