A narrow-band acoustic filter comprises an input and an output, and at least one acoustic resonator pair coupled between the input and the output. Each of the acoustic resonator pair(s) comprises at least one in-line acoustic resonator and in-shunt acoustic resonator that operate together to create a nominal passband. The acoustic filter further comprises at least one capacitive element in parallel with one of the in-line acoustic resonator and the in-shunt acoustic resonator of each of the acoustic resonator pair(s), thereby sharpening one of a lower edge and an upper edge of the nominal passband.