What is roll off rate of a filter?

The roll-off rate of a filter refers to the speed at which the filter attenuates frequencies outside its passband. It is typically expressed in decibels per octave (dB/octave) or decibels per decade (dB/decade). A higher roll-off rate indicates a steeper transition from the passband to the stopband, meaning the filter more effectively removes unwanted frequencies. This characteristic is crucial in designing filters for audio, communication, and signal processing applications to ensure signal integrity.