Building a hush box to quiet a projector
A projector and 120" screen sure are nice to watch TV shows and movies, but having them on the 3rd floor of the house makes the projector unhappy.
Being on the ceiling of the almost highest point in the house, during hot summer days, that projector can become quite hot. And when it does, it tries to compensate by fuelling it’s fans with enough voltage to make them sound like jet engines. (Not PowerMacG5-running-in-single-user-mode jet-engines-loud, but still…)
To try to quiet it down a notch, I built what some people call a hush box.
It’s basically an enclosure that you put over your projector to stop the noise.
Evidently, you need to be careful not to make the projector overheat (which will greatly reduce the lamp life). Projectors emit quite a lot of hot air, so having them in a confined space wouldn’t be a good idea without good ventilation.
So here’s how I did it.
I measured the size of the box I’d need to build to hide the projector and it’s cables. I added 2" on each side, where the air intakes are located on my projector. I added another 2-4" to all dimensions to allow me to place some kind of sound attenuation material inside the box. The plan was to place a 120mm fan behind the box to push cool air in, and another 120mm fan on the ceiling, pulling the hot air out of the box.
I built the box first, using scraps of wood I had, which I attached together using V metal brackets and small screws.
Next, I tried it over the projector to make sure my measurements were correct, and chose a spot to placed the ceiling fan. I climbed in the attic to install that fan. (That’s always fun, with all the pink isolation material in there…)
I then found a nicely sized glass piece that I could use to cover the hole I made for the image. I took it out of industrial 500w lights I had around (yes, they are now much more dangerous to use without that piece of glass!).
Looking for something that would attenuate the sound, I found some scrap pieces of carpet laying around. I cut out pieces of the right size, and place them at the bottom, front and sides of the hush box.
Almost done. I attached the box on the ceiling.
I used a piece of cardboard for the last side, and placed another 120mm fan in there. That will allow me easy access to the projector, if I ever need that.
Here’s the end result:
I’m pretty satisfied with the end result. I have now changed the settings of the projector to ‘High Altitude’, which makes the fans always run at their maximum speed. Even with that, the projector is much more quiet than it was before. Hooray! :)