Nasty Hack for Sub Isolation-That Works

So, we have been doing a lot of research about how to isolate our subs from the floor. In a earlier post, I mentioned that we have weak old floors, and that we rent so that our options are limited. Our subs tend to walk all over, and the floor vibrates making a horrible, extremely unmusical sound. Our local dealer helped sp come up with this ingenious hack:

We have two 54 lb. downward firing Von Schweikert subs. They are on carpet spikes, resting in pucks for the hardwood floor. In order to isolate them, we bought 2 pieces of 1/2" MDF, and 4 gel filled computer wrist rests. The wrist wrests are placed under the MDF, facing up, parallel to one another. The speaker rests on top of the MDF exactly as it would on the floor. The result? The speakers now stay in place. The room doesn't create a racket, and the whole listening experience is more enjoyable.

We tried a number of variations. We tried both 3M and Fellowes brand. The Fellowes worked better, because they are thinner, and have better side wall support. (Plus we've found that 3M is less consistent about thickness.) The thicker pads muffled the sound. We also tried 3 pads instead of two. That too muffled the sound. We found that we want the minimum isolation, so as to loose the minimum tightness and definition.

We'd looked into Vibrapods, but our dealer says this actually works better for isolating speaker. (Vibrapods are designed for components.) We were willing to spend more money, but he assures us that even at hundreds more, he doesn't have anything that works better. (And this is a man who owns a magnetic stand that keeps his turntable completely isolated and is insane about his equipment.)

I know it sounds awful, but really, it works. What little we loose is more than made up by what we gain. For the first time, our subs are living up to their potential.

Joy Elyse
There's nothing "nasty" about something that delivers what you need, especially if it can do it with minimal expense. Thanks for sharing your experience and results as it may help someone else out. Glad that you were able to resolve your problems without going bankrupt too : ) Sean

Thank you for the gel wrist support idea. I've been using racket balls under my stone composite slabs which, in a former life, were analytical balance isolation tables. Possible upgrades for your MDF would be Corian, granite, slate or 1-2" maple. Relatively inexpensive custom maple supports can be had at Though I've yet to try 'em, they are getting rave reviews on their quality.

Dordy, thanks for the suggestions. Paul from VSA had this to say "any of them can work, and probably each will have a sound that is slightly different form the other. Corian, and granite well cost a good bit of pocket change. Even the maple 2 inches thick with enough surface area will cost a good bit as well. So the MDF you are now using is effective and economic at the same time." Maybe we'll experiment some later, but for now we are fairly happy. Also, anything much heavier than the MDF would overwhelm the wrist rests.
Joy Elyse