MatDeck provides various solutions for audio testing software. It provides a comprehensive set of measurements for the quality control of microphone components or speakers. Crucial MatDeck components are the test signal generator, tools for spectral analysis, and built-in equalizer functions capable of correcting imperfections of tested audio equipment. These components are developed as MatDeck toolkits, forms and functions.
Equalizer Toolkit – Graphic Equalizer Form
The Graphic Equalizer Form in MatDeck can be used to tune frequency components of the input signal. The Equalizer filter is designed by setting the values of the amplitude response of the equalizer at given frequency bands by using a 31 slider. The number of frequency bands, that is the number of sliders, is selected according to the common audio standard. Graphic Equalizer Forms are a very convenient tool in various audio testing applications.
Equalizer Toolkit – Equalizer Ten Bands Form
The Equalizer Ten Bands Form is a Graphic Equalizer with a simple and effective filter bank for fast processing. The input audio signal is split into 10 bands using simple IIR filters. The gain in each band can be separately adjusted using the corresponding slider.
Equalizer Inverse Toolkit – Inverse Equalizer Form
The Inverse Equalizer Form in MatDeck is used similarly to the Graphic Equalizer to tune frequency components of the input audio signal. However, the Form offers more flexibility and interactivity compared to the Graphic Equalizer. It also allows users to enter inverse values of the audio system amplitude response at any desired frequency points. The Inverse Equalizer Form is a very convenient tool in various audio testing applications.
Audio Toolkit – Chirp Signal Generator Form
A chirp audio signal with a frequency that is swept in a defined frequency range is a very common test signal that is used for testing audio equipment. In MatDeck, the Chirp Signal Generator Form is used to design a chirp audio signal.
Audio Toolkit – Signal Frequency Analysis Form
MatDeck contains many tools for frequency analysis of a signal, for example fft, dct, periodograms, and spectrograms. However, it is often required to display the amplitude spectrum in a fast and efficient manner. The Signal Frequency Analysis Form is used to display the amplitude spectrum of a given signal. The most important feature is the fact that the user can select the frequency axis scale, and the signal spectrum can be represented using linear scale, or logarithmic (log2 or octave scale) all at the user’s preference.
There are illustrative examples about microphone testing as well.
Example 1: Microphone testing and Graphic Equalizer
In this example, we illustrate how MatDeck can be used in audio equipment testing. In this particular case, we test the quality of the given microphone by recording a test sound. The test sound is a chirp signal whose frequency is swept through the hearing range from 20Hz through to 20000Hz. The recorded sound signal is corrected by using the Graphic Equalizer which is adjusted to reverse the frequency response of the microphone. MatDeck components which are used in this example are: Chirp Signal Generator Toolkit, Signal Frequency Analysis Toolkit, and a Graphic Equalizer Toolkit.
Example 2: Microphone Testing with an Inverse Equalizer Toolkit
In this example, we illustrate how MatDeck can be used in audio equipment testing. In this particular case, we test the quality of the given microphone by recording a test sound. The test sound is a chirp signal whose frequency is swept through the hearing range from 20Hz up to 20000Hz. The recorded sound signal is corrected by using a Inverse Equalizer which is adjusted to reverse the frequency response of the microphone. MatDeck components which are used in this example are: Chirp Signal Generator Toolkit, Signal Frequency Analysis Toolkit, and a Inverse Equalizer Toolkit.