What is the best material to make a hushbox out of? Something dense, like MDF, or something light?

Dense materials will stop the transmission of sound. Lighter materials like foam will absorb some higher frequencies. A dense box with a foam or compressed-fiberglass lining is probably your best bet. But it won't make that much difference unless you completely seal the box, with separate inflow and outgo and a glass cover over the lenses. (Or at least a real tight fitting around the lenses.) Otherwise a lot of sound escapes out through the lens opening.

pretty much what Gary said ;)

mine was made of ceiling tiles, with quilt batting on the inside(use a barrier on the furthest inside lining over batting to prevent lint from entering PJ)

outside was wrapped in duvetyne, frame made of 1x2 I think

most important is acoustic silicon sealant, apply around every crack inside before the batting to make 100% airtight

don't leave the entire front open either, conform to the lenses making a rectangle around them leaving about 1" gap all around

my NEC 1352LC is 99% silent

-Gary

Thanks much, guys.

If you have the ability to vent and feed the hush box, I suggest sealing it buy using Edmunds optical glass.

I'll google that, thanks Don. I have a followup question. I have the venting set up for the box (6 inch vent in the ceiling above the projector), but what's the best way to feed cool air into it? It can't be completely sealed, correct?

When I did mine I had a feed and return inside the box.

no feed needed, the air comes in around the lenses and is sucked out via the vent with fan, my PJ runs cooler with the hushbox installed, no in air feeding

feeding cool air into the box would wreck the PJ with temp changes and such, just use vent pulling out

-Gary

Gary he will need a feed if he uses optical glass.

You can basically built an fish tank around it!
That is what I did with my first "diopsable" bulb box, but for a CRT machine it will have to be much bigger of course and you will need to be able to put some kind of an intake/exhaust on it...

All the parts are available at a fish/aquarium store.

Hope this helped

Martin

Since when is a Sony G90 a disopsable unit? I did this for the G90 as well as my new RS1. Did have to be that much bigger than the unit.

Don
I too am the proad owner of a G90 (along with couple of marquees) and I consider them to be the best as far as pjs are concerned!


I was referring to my "top of the line" (..for then! and my lack of knowledge!) first dlp,: which was an infocus x1

Martin

Yeah those G90s are really something.

Gary he will need a feed if he uses optical glass.

of course, sorry for the confusion

-Gary

I have used 1/2" veneer faced plywood (stained) and lined it with ceiling tiles (inside) fiberglass type with the lens open for now but will be sealed off with closed porse foam. I also have two fans one for cool air coming in and one for extraction. It is not dead quiet but very quiet.

I used 1/2 MDF. It saves the step of building a seprate frame.
http://www.curtpalme.com/forum/album_page.php?pic_id=634&mode=previous
I initially designed for 3" of sound absorbing material. The MDF alone made a bid difference, adding 2" egg crate foam helped.

All hard surfaces should be lined with at least an open cell foam.
http://www.curtpalme.com/forum/album_page.php?pic_id=638&mode=next

Here's my hushbox pictures and design: http://www.curtpalme.com/Hushbox1.shtm

Kal

AJF,

Where did you purchase the temperature readout unit?

Gabe

It's a Scythe fan speed controller w/temp readout for a PC. Got it on sale at MicroCenter.

Runs 4 fans, 4 RTD temp probes with audible fan fail alarm. I really only needed the 2 fan unit but I bought this one it was only 8$ more.