Huron & SNAP Documentation

Calibrating Speaker Arrays
THE SIMULATION TOOLS
Azimuth
Elevation
Roll
Figure 24 — Positive azimuth, elevation, and roll of a sound
source
Given the forward-facing vector of a sound source, azimuth is
defined as a rotation of the vector about the X-Y plane;
elevation is a rotation towards the Z-axis; and roll is a rotation
of the source about the direction of the vector itself.
When rendering a simulation to a speaker array, it is desirable
to calibrate the amplifier gains so that each speaker contributes
equally to the sound pressure level at the centre of the array.
This will eliminate unbalances in the array so that panning is
smooth. The technique described below is valid only for arrays
where the speakers are equidistant from the centre of the array.
A sound pressure level meter can be used to measure the output
power of a given amplifier / speaker configuration. Feed a
constant input source such as a 1kHz sine wave into one
speaker at a time and measure the resultant on-axis output
power at a fixed distance (say 1 metre) from the speaker.
Adjust the amplifier gains so that each speaker has the same
volume with the given input source.
HURON TECHNICAL MANUAL PAGE 71