anechoic chamber


PH: The anechoic chamber is in the Acoustic Research Unit at the University. It's 5 x 4 x 2.6m in size, and as you can see, its primary function is to test the noise levels of various bits of equipment. The walls are entirely covered with those foam pyramidy things you can see in the photo, and the floor is suspended over some more of them. Playing in there is a bit odd, cos the sounds don't match what you see: whether you realise it or not, you're conditioned to expect spatial information when you make a noise in a room, and in an anechoic chamber, you're denied this entirely. You hear the noise of your instrument, but nothing else at all.

We had a blast: the room is incredibly detailed, and we had a lot of fun blowing microtones to get the difference tones out of them, and playing around with the noise of the keywork on our horns.

In the same unit they've also got a totally reverberant room, which they use for testing soundproofing. We didn't get time to nip in there, but that is one scary acoustic. No idea how you make one of those: it looked like a normal, medium-sized room, but every frequency came back at you like a wave. Very odd.

CK: I think my favorite of the locations was the anechoic chamber. In this place, the difference between what you hear & what you see is extraordinary - you see these LONG yellowed cones of foam closing in on you from all sides, but you hear NO walls, NO floor, NO floor or ceiling, no surfaces around you at all. One result of this isthat the small sounds which would normally be drowned out in the backwash of reverberance become more noticeable - sounds of breathing, crackle of spittle, fingers on keys, the reed just starting up and stopping...and one's own hert, breath inside, movements - event he blinking of your eyes, reminding me at least that as a child I had time and energy to listen to all these sounds from within. This emphasis on the physical sources of our sounds made me very happy at the time, and I still yearn to repeat the experience now. Of course, the anechoic chamber was also the space furthest from day-to-day acoustics (unless one is a hot air balloonist).