Audio Analyzer for acoustical and
The ATB PC Pro measurement program in
connection with the soundcard of a computer is a precise
and extensive Audio Analyser.
THD and IMD
The Audio Analyser is for loudspeaker
development, optimizing room acoustics, installation of
Car HiFi systems and measurement calibration of surround
The Windows ATB PC measurement
program is built around the success of the professional ATB
precision program. It offers all the functions of the
Windows operating system.
The measurement signal by an internal
generator function is generated by the soundcard. With
our external generator function, a CD or DVD player
generates the measurement signal. Therefore, older
computers with simpler soundcards are adequate for the
measurements. To be independent from the quality of the
soundcard the program has an extensive correction
function to compensate the less than ideal soundcard
The ATB PC has its own Mixer for the
soundcards. Therefore, the selection and setting of the
Soundcard is easy to handle.
The special M-PN signal in
combination with a new correlation method avoided the
frequency faults of the MLS soundcard systems. This also
allows an acoustical measurement without determining the
distance. In addition, no time windows need to be set.
This makes the operation as easy to use as a 1/3 octave
analyser. For setting the subwoofer in home cinema
systems there is a mid-high and a subwoofer signal.
The Signal 13 is for the distortion
measurement. For the THD measurement is the sine wave
signal. It is also for nonlinear distortion measurement.
Wolfgang Klippel, Germany, describes
the distortion from nonlinear systems.
The basic for this measurement is a
generator signal with consist of two sine waves. The
signal is modulated at the nonlinear transfer response
of the system under test. The result is the THD and the
The Signal 13 was developed from the
Kirchner elektronik company. The signal consisting of
the heterodyne of two sine waves with the ratio of
1:1,3. This gives a non-static signal. The signal 13 is
for testing distortion like THD, IMD und nonlinear
The time domain of the Signal 13
The frequency spectrum of the Signal 13
The time domain of the signal shows
an always-varying wave. The signal excited all
resonances of the unit under test. The resonances and
the nonlinear transfer function show a spectrum with a
great number of distortion frequencies.
For the calculation of the Q-index
the amplitude of distortion frequencies are added and
set into proportion to the amplitudes of the Signal 13.
This measurement shows the quality of a device.
So that the measurement data can be
further processed with a CAD program or saved in an
existing database, the ATB PC has an export function.
The ATB data can be converted into following formats:
MLSSA, LAUD, IMP, LMS and
The program also has an
Auto-Export function for
simple processing or evaluation of the data with user
The ATB PC Pro measurement system
Test box for impedance and
Frequency range of the microphone
DVD and CD for test signals
20Hz – 20kHz + 0.3dB