In loudspeakers, the part/s of the crossover that block/s higher frequencies to let lower ones pass.
An electronic device that modifies the amplitude of a signal as a function of the signal frequency content and filter cutoff frequency. Frequency components above the cutoff frequency are attenuated, while those below are passed with little or no change. The cutoff frequency is defined as the signal frequency at which the filter output is 3 dB below the input.
A circuit that passes frequencies below a specific frequency (the cutoff frequency). Frequencies above the cutoff frequency are reduced in amplitude to eliminate them.