An Orthodox church as a building expresses the Eastern Orthodox spirituality - all the details and general aspects have a deep and philosophical meaning. The architecture, being an illustration of the character of the Orthodox Church liturgy, has become a natural component of the cultural landscape of Poland and Eastern Europe. Acoustic research into Orthodox churches has so far been marginalized. Up to now, only a few churches of this type have been studied. The article is a review of the acoustic environment of churches in Poland. Churches, differing in terms of size, architectural style and other quantities, were chosen and acoustic measurements were made. The results of the measurements have been analyzed and collated. In particular, a detailed analysis and comparison was made for reverberation time as a function of frequency, due to the largest differences in this parameter between the rooms.

This article discusses the innovative application of a Cartesian robot manipulator with acoustic feedback for calibration and precise positioning of a string-excitation element in investigating stringed instruments. It describes an experiment in which an acoustic guitar string is automatically excited with different guitar picks. The robot’s end effector positioning system utilizes limit switches, acting as a mechanical sensor, which provides feedback to the linear actuators that are equipped with stepper motors. The authors detail the research challenges they faced and propose a positioning algorithm that makes use of a microphone as an acoustic sensor, improving the calibration of the end effector’s position.