A circuit board module for a sound transducer assembly for generating and/or detecting sound waves in the audible wavelength spectrum includes a circuit board, which features a recess with a first opening. At least a part of a MEMS sound transducer is arranged in the area of the first opening, such that the recess at least partially forms a cavity of the MEMS sound transducer. The recess features a second opening opposite to the first opening, such that the recess extends completely through the circuit board. A sound transducer assembly includes such a circuit board.