LOUDSIM
is a Windows based loudspeaker simulation program. It can be
used to calculate the response of a moving coil drive unit
mounted in a closed or a vented (reflex) enclosure or on an
infinite baffle. The driver (Thiele) parameters, which may be
obtained from the manufacturer, are first defined together
with the cabinet dimensions. The program will then calculate
the speaker amplitude response (Sound Pressure Level - SPL),
impedance, phase shift and efficiency at any given frequency,
and it will also give the optimum vent loading for a reflex
enclosure, as illustrated in the screenshot below.
The program also
provides a graphical output showing the loudspeaker or woofer
bass response over the frequency range of 10 to 500Hz
together with the speaker impedance (lower trace). These
curves may be plotted in colour and the response for
differing enclosures or drive unit parameters may be
superimposed for ease of comparison. The screenshot below
shows the predicted performance of the driver, defined in the
above example, mounted in a vented box with optimum vent
volume. The amplitude response is essentially flat down to
40Hz and then falls away rapidly at 24dB per octave. The
impedance curve exhibits the characteristic double hump with
a minimum at 30Hz - the Helmholtz frequency.
The next
screenshot shows the step response of the above speaker which
exhibits considerable ringing at around 30 Hz.
The
program is easy to install and use. Many examples of popular drive units and loudspeaker
designs are
included together with full documentation. The speaker details and program
settings are stored on exit to allow the same parameters to
be used on restarting. The minimum hardware requirements are
any IBM 386 compatible PC with coprocessor running Windows
9x/NT/Me/XP or Vista. This is an EDA - Electronic Design Automation
- product.
• Click here to purchase the full registered version of LOUDSIM.
LOUDSIM : 09/04/10