Archivox Room Impulse Response Measurement

Used to measure multi-channel acoustic room impulse responses and loudspeaker directivity.

This user interface for Matlab™ allows for simple impulse response measurements with multiple channels of input and output through any sound interface with ASIO drivers on PC or Core Audio on Mac. The polar scan feature can also be used to measure loudspeaker directivity or diffusion coefficients of architectural wall panels.

Room Impulse Response Measurements
Room impulse response measurements can be conducted by placing a loudspeaker and microphone in positions appropriate to the use of the room. Preferably, the source should be the actual loudspeaker that will be employed when the room is in use or a source that emulates the actual source. Omni-directional sources, like dodecahedral loudspeakers are often used to simulate music ensembles or other natural sources. The receiver should be placed at a representative listening position, or in the case of large seating areas, many measurements throughout the listener area should be taken. Impulses collected with this software can be saved for future analysis or for making auralizations of the space. See ISO standard 3382 for more information.

Polar Scan Measurements
Polar scan measurements are initiated by placing the microphone in the first position and pressing "Go!." When the first measurement is complete the microphone is moved the number of degrees specified in the "Resolution" box and the next measurement is taken by pressing go until the arc is complete. To measure loudspeaker directivity the loudspeaker must be placed in the center of a large empty room such that the first reflection from any surface arrives substantially after the direct sound. The signal can then be cropped to include only the direct sound. The relative magnitude of the direct sound in each direction composes the directivity of the loudspeaker. If a measurement is interrupted or fails for any reason the "Go back" button allows repeating previous positions. When all measurements have been collected the "Save" button will write a multi-channel .wav file to the location of your choice. See AES standard AES-4id-2001 for more information on diffusion coefficient measurements.

For more information visit: http://www.archivoxacoustics.com/RIR/RIRmeasure.html