Example: how wood turns vibration into noise

When noise becomes a low frequency vibration...

I made this short video with my mobile phone to show how an airborne noise (the buzz from my mobile phone when it's set to "vibrate") becomes a loud, intrusive noise when it makes direct contact with a wood surface. This is the same way that simple impact noises like walking, opening and closing doors and drawers, or even the bass from your stereo or home theatre system can go into the walls and transmit to your neighbors or to other rooms in your home.

I placed different materials underneath the phone while it was buzzing on top of the wood table. You can hear how each of them (even the thin sheet of cork) make a difference in reducing the noise transmission through the wood.

One point: while I was recording this, I noticed that QuietRock (being the "hardest" of the surfaces) still transmitted a tiny bit of vibration to the wood beneath it, while at the same time dampening the buzz. That's an example of how I think that QuietRock in tandem with Green Glue is more successful than using it alone.

These materials -- when used as solutions for different noise problems -- can have some effect on reducing noise transmission for a relatively low cost.

For example, anti-vibration pads (like the one shown here -- sold at soundproofing.org) reduces noise from appliances like washing machines, dryers, dishwashers, and floor fans.

A single sheet of cork might help in reducing vibration transmission under a pair of stereo speakers on your computer.

A layer of QuietRock drywall (especially if glued on top of your existing drywall with a coating of Green Glue) will reduce stereo-vibration noise and other noises from transmitting through your walls.

If you're redoing your floors, a layer of cork between your surface floor and your subflooring might reduce some impact noise. But if you're going deeply into a remodel, look into decoupling your subfloor from the building frame. Or take some other measures to stop heavy vibrations from transmitting through your floors, such as a floating floor.

Here's the video. Hear it for yourself (best with headphones)!

Comments

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