The contribution focuses on the experimental basis of acoustic signal evaluation in a frequency domain using experimental data acquired by a sound-level meter Mediator 2238 from scanning of the acoustic signal arisen during the rock disintegration process by means of rotary drilling. The paper also focuses on the model of mathematical processing of parallel-scanned acoustic signal. The research field is complex due to properties of the process and the subsequent proper physical application of measured values and the design of a proper mathematical model of the process. The research is based on a conception that a signal of mechanical vibrations, i.e. also an accessory acoustic signal, carries an information on a stage of disintegration process, which might be used for its identification, control and optimization of rock disintegration process. As the problem is very extensive, many patterns of several science areas have to be considered and coordinated, such as rock disintegration, acoustics, scanning and processing of monitored signals, not only during the experiments but also at their evaluation and finding new relations and models.