Put some kind of shock-absorbent material between the mounts between the amp and box. I've read the rubber from a bicycle inner tube works. Any kind of soft absorbent material will help. Maybe some very thick soft rubber washers between the amp and box?
Ok man thanks i might just build a little amp rack and has it look like its mounted on there like in the front but its not actually on the subwoofer box.
If your box is well built, then it should be sturdy enough to not really even shake. Canaan's install has 2 DD 3515s on 2krms and his amp is right on the box. The outside does not shake at all. But just incase, you might just want to put another layer of mdf on the area of the box that you are mounting your amp.
It isn't the vibration from the soundwaves that kills the amps it is box flex. Add an extra piece or two of mdf under the amp or add squares under each mounting hole instead of having the whole amp against it, this will work. One of my other hobbies was R/C helis and vibrations use to cut through wires so I know a little about vibration, balance. Adding an elastomer doesn't eliminate vibration but moves it up/down the scale at which it will occur, could be worse than what you had. Either way you cannot get away from airborn waveform and once it hits the amp will vibrate it on its own, just keep it away from the flexing wood...Polo.
