Application Catalog
|
|
| 9 - Sound Pressure Analysis of a Loudspeaker<TR,DS> |
Overview
Closeup |
A loudspeaker produces sound when the current in the voice coil interacts
with the magnetic field of the magnet causing the vibration plate connected
to the coil to vibrate. The general requirement of the loudspeaker is to
produce uniform sound over a wide range of the frequencies. JMAG calculates
the sound pressure using the electromagnetic force obtained by the magnetic
field analysis and the eigenfrequencies calculated by the structural analysis.
This example presents the use of a magnetic field and structural analysis
to obtain the frequency characteristics of sound pressure when the Lorenz
force acting on the voice coil is constant regardless of the frequency. |
Sound Pressure Level
The frequency characteristic of the sound pressure level at the front center
of the loudspeaker is indicated in Fig. 1 and the sound pressure distribution
at a frequency of 200 Hz and 2000 Hz are indicated in Fig. 2.
The frequency characteristics of the sound pressure level show that the
loudspeaker has a uniform output above 100 Hz, but is not suitable for
use at lower frequencies under 100 Hz. |
Closeup |
Closeup |
|
|
Updated: 2011-07-12
|
|
|
