An arrangement is provided for detecting a damage of a filter fabric (8) of a disc filter (1) at a disc filter unit comprising disc filters. The arrangement includes a measurement bar (20) that includes two or more microphones (21), a store (45) including stored sound samples, at least one alarming means and a processing arrangement (43) for analyzing online sound or sound samples captured by the microphones (21). The processing arrangement (43) is connected to the microphones (21), the store (45) and the at least one alarming means. A method is also disclosed for detecting a damage of a filter fabric (8) of a disc filter (1) at a disc filter unit.