About MeasureTransferFunctionThe software MeasureTransferFunction (MTF) allows the convenient measurement of the transfer functions of acoustic systems. It uses logarithmic sine sweeps for the broadband acoustic excitation of the system under test and supports the measurement of two sweep responses at different positions. The measurement principle is based on the method by Farina (2000), which is explained in more detail in the manual (included in the download). The main strength of the method is that it allows finding the linear impulse response of the system even when individual system components (e.g., the loudspeaker) generate harmonic distortions. This means also that low-cost (consumer) audio hardware can be used to perform the measurements. The software requires an audio interface that supports a sampling rate of 96~kHz and 24 bit quantization for the simultaneous playback and capturing of audio data. An example for such an interface is the USB interface Aureon Xfire 8.0HD for about 100 Euros.
The primary motivation for the development of this software was the measurement of the volume velocity transfer functions between the glottis and the lips of 3D-printed physical models of the vocal tract. However, the software MTF is not limited to the use case above but is also applicable, for example, to the characterization of loudspeakers or other audio components and to room acoustics measurements.
MTF has been developed in C++ for the Windows platform and is free of charge and open source.
This demonstration video shows how the software is used to measure the transfer function of tube models of the vocal tract.
Screenshot of the program: