The Shure Beta 91A is a boundary microphone that can double as a kick drum mic, as it can capture the punch and attack of low-frequency instruments such as kick (bass) drums. It features a wide frequency response well suited for capturing a variety of audio signals such as organ and piano. The flat, boundary design also aides in producing a strong, solid low-end response, as well as make it easy to mount inside of a bass drum. The Beta 91A is ideal for both recording and sound reinforcement alike.