Listening to music can affect the functioning of the brain. The main aim of the research was to investigate the impact of listening to music for string instruments on changes in EEG waves and rhythms. Twelve several-minute pieces of classical music were selected. They differed in character, date of composition and number of performers. The study group was divided into musicians, who declared playing a string instrument, and non-musicians. The recording of the EEG signal for each person consisted of 12 segments registered during listening to music. Based on received signals, a comparative analysis was performed using the main frequency value and the main standard deviation value for each electroencephalography wave (alpha, beta, delta and theta). In order to compare the degree of dispersion of the data, interquartile range values were calculated. The student’s t tests and F tests were then performed. Based on statistical analysis, it was noted that there are statistically significant differences in frequency values between group of musicians and non-musicians.