Can speaker cabinet vibrations be fixed?


Hi,

Recently I noticed that bass notes cause the cabinet/housing of one of my loudspeakers to vibrate, thus, distorting the sound of the notes. The vibration is at its worst when the speaker reproduces 50-80 hz test tones.

The cabinets for my speakers appear to be constructed of laminated particle board, the pieces of which were assembled using some sort of wood glue or possibly epoxy. The speakers measure 16"W x 28"H x 10"D.
Though the vibrations seem to be originating from the back piece of the speaker, I find that if I place my palms on the left and right hand sides of the speaker and then apply a little bit of pressure inward, the vibrations cease, and then the speaker operates normally once again.

These are not audiophile quality speakers, but if I can make a repair (I refoamed the woofers a couple of years ago), I'd really like to hang on to them.

If it's possible to fix this problem, any advice on how to do so would be very much appreciated. Thank you.
jsangelo
Another cheap tweak to significantly reduce cabinet resonance is to apply DynaMat, or one of it's clones, to the inside to the cabinet. Dynamat, and similar products, are sold at auto parts stores for damping metal panels in cars to which speakers are attached. It is a simple, constrained-layer damping material that consists of a sticky, asphalt-like layer mated to a layer of aluminum. It is Very effective at damping vibrations and very simple to apply; simply peel-and-stick to the inside cabinet walls. Costs about $20. for two 8"x10" sheets. Fast, simple, effective, and relatively cheap. Then, if you're really ambitious you can internal bracing. But, you might need it by then
You should make sure that the screws that hold your woofers in place have not come lose.
Agree with Sounds real, periodically check all your fastening screws.
Screws will back out over time from vibrations in particle board including shifts in climate especially with medium and high density fibre boards when directly fastened into.

Many speaker cabinets of today are constructed with inexpensive mdf and hdf which are poor materials to directly fasten a screw into, ask any competent cabinet maker.

However checking for loose screws should be part of your system maintenance which ever fastening method used and material your speaker cabinets are made of.

From your description you will most likely find this is the problem. You may get away with simply tightening the screws.
Or
There are many great adhesives available, buy one that is suitable for the screw and particle board.

For the drivers themselves use a drop of motor cycle nut and bolt adhesive, Lock Tight brand or similar.

Stiltskin: unfortunately, no screws were used in the construction of these speakers, but I wish there were, as merely tightening them would've been easy and the first thing I would've checked.

I'll probably need to add some adhesive and/or go with some braces as Usblues and Bradearles suggested. Trying to find suitable screws for cheap, laminated particle board could be a problem, though.

Thank you, everybody, for excellent suggestions all around. ;-)
Never took one apart.....Don't builders use threaded inserts to secure drivers? I would! And some kind of hard, closed cell foam as gasketing.