Design and evaluation of a microphone array monitoring system for smart music hall is addressed from a multidisciplinary viewpoint, with cello section rehearsal as a specific case. It is recognized that, for a typical music hall a successful performance of symphonies, string music, or ensembles depends upon the quality of each instrument section and their perfect cooperation. Therefore, sectional rehearsal is the basic requirement of such performances. Professional orchestras generally can obtain professional guidance from conductors and section leaders to conduct standardized sectional rehearsals. However, it is generally difficult, if not impossible, for unprofessional symphonies orchestras organized by amateurs such as schools, government entities or enterprises to find good rehearsal guidance, thus hindering the further popularization of symphonic performance among music lovers of various communities. Thus there is an urgent lack of quantitative guidance way for amateur orchestras. With an advantage of improving acoustic signal processing, the technology of microphone array has been widely applied in sound source localization, noise reduction and sound amplification. Thus, in view of the lack of a qualitative sensing way for teaching assistance of sectional rehearsal, a microphone array monitoring system is designed and evaluated for smart rehearsal teaching of the cello section. By optimizing the parameters of the microphone array according to the acoustic characteristics of the cello, it aims to realize real-time monitoring of the volume, pitch and other parameters of the cello for the smart teaching. The experimental results are provided to show the effectiveness and feasibility of microphone-array-assisted smart teaching of cello sectional rehearsal.