My subwoofers Dance across the hardwoods, why?

[bigbardmusiq]

This question has probably been answered many times before but I'm new to this. When I crank-up the volume my dual subs start doing the tango with each other. I have tried the Dayton spikes, tried lifting the boxes 2.5 inches from the floor with furniture style feet, and I've tried those big rubber feet (2in diameter, 1.5in tall). There both down firing style boxes that I constructed myself. I'm open to any suggestions!

[Fairlane64]

This may sound crazy, but have you tried putting something heavy on them to see if they will stay in place? You can purchase lead ballast like used in race cars for around $1.25 ~ $1.75 a pound (sometimes cheaper if you check at a local shop that sells parts to racers). It can easily be encased in a wood box and set on top of the speaker to help keep them in place. You might try something heavy first just as a test to see if they will stay put with some added weight (or just push on them while they are playing to see how much force is required to make them stay put). I'm guessing 20 to 30 pounds might do the trick.

[Pete Schumacher ®]

Almost guaranteed that if the subs weren't down-firing, the rubber feet would have done the trick.

Fairlane is right. All you need is more mass on the enclosure and it will stay put just fine.

A fine demonstration of the need for a heavy enclosure when your woofer is capable of serious motion, and a tailor made argument for using dual, opposing woofers when constructing a sub.

[fastbike1]

Or perhaps an argument for avoiding downfiring boxes. Remember, Physics is the Law, not just guidelines

Almost guaranteed that if the subs weren't down-firing, the rubber feet would have done the trick.

Fairlane is right. All you need is more mass on the enclosure and it will stay put just fine.

A fine demonstration of the need for a heavy enclosure when your woofer is capable of serious motion, and a tailor made argument for using dual, opposing woofers when constructing a sub.

[rudyjakubin]

This question has probably been answered many times before but I'm new to this. When I crank-up the volume my dual subs start doing the tango with each other. I have tried the Dayton spikes, tried lifting the boxes 2.5 inches from the floor with furniture style feet, and I've tried those big rubber feet (2in diameter, 1.5in tall). There both down firing style boxes that I constructed myself. I'm open to any suggestions!

I have a 12" Down Firing sub and it took 35 lbs. to keep it in place.
I watched Lord of the Rings disc 1 on BlueRay last night. The sub stayed put but loose items on a shelf vibrated off.

[bigbardmusiq]

This may sound crazy, but have you tried putting something heavy on them to see if they will stay in place? You can purchase lead ballast like used in race cars for around $1.25 ~ $1.75 a pound (sometimes cheaper if you check at a local shop that sells parts to racers). It can easily be encased in a wood box and set on top of the speaker to help keep them in place. You might try something heavy first just as a test to see if they will stay put with some added weight (or just push on them while they are playing to see how much force is required to make them stay put). I'm guessing 20 to 30 pounds might do the trick.

No that's not crazy at all, holding a little bit of pressure will hold them in place. I have been racking my brain trying figure a good way to add more weight. My day job is welding (metal everywhere) I just need a good idea.

I also turned the subs on there sides and place them on some Rockler bench cookies. That fixed it, but it seems to drop the bass 25-50%

[dthomas]

No that's not crazy at all, holding a little bit of pressure will hold them in place. I have been racking my brain trying figure a good way to add more weight. My day job is welding (metal everywhere) I just need a good idea.

I also turned the subs on there sides and place them on some Rockler bench cookies. That fixed it, but it seems to drop the bass 25-50%

Turning them on their sides causes you to lose some of the reinforcement you get from the floor when they are downfired. So not surprising that you would hear a drop in overall output.

Go to a countertop store and see if you can get some 2" granite peices cut to fit the tops that may be enough weight to hold them down. Or you could do a poured concrete top for them. Anything that adds enough mass will hold them in place.

[Chris Roemer]

Turning them on their sides causes you to lose some of the reinforcement you get from the floor when they are downfired. So not surprising that you would hear a drop in overall output.

Go to a countertop store and see if you can get some 2" granite peices cut to fit the tops that may be enough weight to hold them down. Or you could do a poured concrete top for them. Anything that adds enough mass will hold them in place.

A big old heavy pocket watch works too.

[MSaturn]

Brilliant Pebbles will absorb all stray frequencies and increase the output of your subwoofer at the same time. If this fails, you may need a Clever Little Clock like CR.

[bigbardmusiq]

wow, a little piece of Acoustic Foam 1-1/2 under the rubber feet stop it!!!!!!!!!!!

[Pete Schumacher ®]

wow, a little piece of Acoustic Foam 1-1/2 under the rubber feet stop it!!!!!!!!!!!

It's still jumping up and down, but now the acoustic foam is just acting like a shock absorber and adding enough friction with the floor to keep it still.

What happens when you put a small item on top. Does it stay put?