AG500 articulograph – The only apparatus of this kind in Poland is the equipment of the Department of Speech and Language Pathology and Applied Linguistics, MCSU, where our EMA project is based. The articulograph is one of the most modern research tools and makes it possible to record, present graphically and assess the movements of mobile articulators (the lips, the tongue, the jaw and the soft palate). This recording system allows one to inspect and analyze dynamic 3D movement visualizations synchronized with parallel audio.
16-channel microphone-array recorder/processor (MARP-16) – It was designed and built for the needs of the project to facilitate multichannel audio data acquisition (Fig. 1).
Fig. 1. The 16-channel audio recorder/processor and circular microphone array used in the study
Unlike similar products on the market, this device is characterized by uncompromising design and construction. The input circuits consist of low-noise, broadband microphone amplifiers and high-speed successive approximation register (SAR) analog-to-digital converters that are dedicated to measuring equipment. The acquisition and pre-processing of the recorded audio data is performed by a 32-bit floating point digital signal processor (DSP) with the Cortex M4F core. The audio data acquired during the recording sessions is stored on an SDHC/SDXC memory card in the form of 16-channel WAV files. The device is controlled from the main computer equipped in an opto-isolated interface to minimize interference. The circular microphone array (cf. Fig. 1) is equipped with Panasonic WM-61 electret condenser capsules having a linear frequency response.