Hemi-Anechoic Chamber Construction

[-The_Mask-]

If you don't hear it, doesn't mean it isn't there of course.

[Orion]

Originally Posted by crmaris

all the rest equipment is in an another building and I just remote control the sound meter and the rest of the stuff.

So the load tester's cables (and other load equipment cables) will be routed from the other building and come into the anechoic chamber through some kind of hole in the wall, correct?

[crmaris]

The procedure is different, however I am afraid that I cannot reveal more about it.

[Internet]

Originally Posted by crmaris

Once the door closes, you can only hear your thoughts in there Will post more pics of course once it is fully ready.

Are you sure? This video says you can hear more than your thoughts.
https://www.youtube.com/watch?v=mXVGIb3bzHI

Noob question: what's the practical difference of having those big edges on the foams? Asking because the pictures of anechoic chambers I'm seeing have big edges on the foams, but in yours the edges are much smaller.

[jonnyGURU]

Originally Posted by Internet

Noob question: what's the practical difference of having those big edges on the foams? Asking because the pictures of anechoic chambers I'm seeing have big edges on the foams, but in yours the edges are much smaller.

You mean like this one?

[Internet]

Yes.

Wondering also if those things can compete against strong thunderclaps. Had one big storm here this morning, all the windows here were vibrating...

[crmaris]

Searched thoroughly about this and talked to several experts and told me that you don't need those long fins unless possibly you need to measure really high noise levels where you will expect strong echoes in the chamber. Actually they suggested to use a flat (but really thick) surface however I wanted something looking nice, so I went the extra mile and invested on this material, which is new and really expensive.

Learned so many things about anechoic chambers the last couple of months and I can safely state know that I know how to build a perfect one from scratch. Another fact, the ideal chamber should have unequal and non parallel surfaces, however this is a real design challenge. But for my purposes (low noise measurements) there is no need for such extreme designs. I just paid extra attention to the chambers insulation from external noises. Although I live in a not so noisy environment, I still invested on a 52 dBA door and the walls are around 60-70 dBA suppression. The top of the building has 50cm thick ceiling, including special insulation, and the bottom is over 60cm, including two layers of insulation.

[crmaris]

the chamber that Jonny showed is a fully anechoic one, which isn't suggested for IT equipment. For IT hemi-anechoics are most suitable.