subwoofer buzz - how to eliminate it

@grislybutter Wrote:

At low frequencies, it vibrates, like it wants to fall apart. 

Just a guess, sounds like you are overdriving the sub.

Mike

@ditusa sorry for my stupidity, how do I overdrive it? 

I am not setting the volume on my amp high, just medium. The gain setting on my sub is at 50%

forget the springs. all you need is the Auralex.

You do not want to isolate the sub from the floor. You want to do exactly the opposite which is fix the sub to the floor. This is what spikes are for. Use three, two up front and one in the rear. Trying to isolate a sub from the floor is folly. Bass waves are very powerful. If you have a bad floor that resonates it will do so even if the sub is mounted on the ceiling. If the floor is that bad the system need to go in a room with a sturdy floor. Spiking the sub to the floor keeps it from shaking so much. Any shaking or vibrating is distortion. 

 all you need is the Auralex

and 

fix the sub to the floor

are they conflicting suggestions?  My floor is pretty rigid, hardwood on concrete.