Princeton University  

Facilities


The 3D3A Lab consists of three adjacent sections:

  1. The Anechoic Chamber
  2. The Listening Room
  3. The Control Room


1. The Anechoic Chamber


The 3D3A Lab is equipped with a highly reconfigurable anechoic chamber that was built in-house and that has adjustable/removable walls which can be moved on casters. It measures w: 3.0 m, l: 3.5 m and h: 2.2 m. The walls, floor and cieling are covered with 1 foot x 1 foot melamine square wedges. The wedges are 8 inches deep and give the chamber a cutoff frequency of 425 Hz. The chamber is lit with strings of green diode lights that give it a pleasant ambiance. The lighting and the fact that the chamber is not soundproof, make it a pleasant environment for human test subjects.

Two binaural (dummy head) microphones are availble for measurements in the anechoic chamber and the listening room. The first is Fritz, a Neumann KU 100:

and the second is Lars, a B&K Type 4100 (datasheet):


2. The Listening Room


The 3D3A Lab's Listening Room was designed to be similar to a typical home or studio environment. The level of sound reflection can be controlled by repositioning absorptive fiberglass panels (RealTraps RFZ Panels). There is a wide selection of loudspeakers ranging from passive concentric to electrostatic loudspeakers and powered subwoofers. A survey of the directivity of loudspeakers in use at the 3D3A Lab can be found here.


3. The Control Room


The control room is equiped with state-of-the-art audio equipment, computers, processors, and acoustical diagnostics tools. The equipment includes: