Loudspeaker and Electroacoustic Test Software News
Sonic beacon is a PC-based test and
measurement system for the testing of loudspeakers and other
electro-acoustic products using commercially available Windows multimedia
sound cards. Sonic beacon will perform Frequency and Phase Response,
Harmonic and Intermodulation Distortion, Polarity, Impedance, Sensitivity
and SPL as well as other FFT and Real Time Analysis tests, Sixteen bit
sampling rates up to 192 kHz and FFT lengths up to 128K points are
supported. Two-channel WAVE File Open, Signal Generator, Arbitrary
Filter, Oscilloscope, Spectrum Analyzer, Data Logger, SoundIO
and WAVE File Save modules are included in this release.
The Wave File open module converts
uncompressed PCM audio (.wav) files to the data format passed from module
to module in sonic beacon processes.
The Signal Generator produces sines, squares, triangles, ramps, impulses, white
noise, MLS sequences and waveforms from the clipboard. It can also sweep
any of the fundamental signal types in a linear, logarithmic or
exponential fashion. Multi tone signals, such as those needed for
inter-modulation distortion measurements, may be generated by cascading
The Arbitrary Filter module performs
transversal or FFT filtering using any of six user defined frequency and
The dual channel oscilloscope in
addition to 4096 record averaging also allows the user to select which
part of the displayed time domain signal (such as the sound reflected
from a surface) to exclude from processing in subsequent modules.
The Spectrum Analyzer performs FHTs;
FFTs and cross correlation on two channels of time domain data. It can
display frequency domain data (amplitude, phase and impedance) on its
view screen using a variety of different X and Y-axis scaling.
Monochromatic line and multicolored bar plots are available in a variety
of styles. Frequency calibration corrections may be applied to the
displayed data without affecting the time and frequency data passed to
subsequent modules. Non-weighted averaging (1, 2, 4, 8… 4096 records) and
smoothing (0, 1, 2, 3… 32 records) may also be applied displayed signal
traces. Second, third, fourth, fifth and total harmonic as well as second
third and fourth order inter-modulation distortion modes are also
Module can record and play 5000 to 192,000 S/S audio signals on any PC
sound card that is compatible with Microsoft Windows WAVE multimedia
services. Multiple sound cards and
mixers are simultaneously supported with independent level, latency and
frequency response calibration.
The Data-logger module can display
color keyed data plots in either the time or frequency domain on any of
its three variable axes’. It can be used stand-alone (visual editor) or
in accumulate mode. It also provides signal gain and delay adjustment as
well as convenient sum and merge functions to
combine near and far-field loudspeaker measurements.
The Wave File Save module converts
digital signal data generated by a stream of process modules to RIFF format and saves it to disk as a
PCM Waveform audio file (.wav).