(Elektrik, Elektronik) A low-pass filter is a filter that passes low frequency signals but attenuates (reduces the amplitude of) signals with frequencies higher than the cutoff frequency. The actual amount of attenuation for each frequency varies from filter to filter. It is sometimes called a high-cut filter, or treble cut filter when used in audio applications
A low pass filter is used to filter out higher frequencies in a sound so that only the lower frequencies can be heard The point above which the frequencies are filtered out is known as the cutoff frequency
A circuit that passes low frequencies and reduces the amplitude of high frequencies above it at a fixed rate For instance, when one sets the low pass filter control on a subwoofer to 80 Hz, the audio signal below that frequency is passed on to the subwoofer driver unaltered, while the portion of the signal above 80 Hz is attenuated If the filter uses the standard 12 dB per octave attenuation, the signal level at 160 Hz will be lower by 12 dB and at 320 Hz, by 24 dB As with high pass filters, low pass filters can be designed to act anywhere in the audio frequency range
A network of components which attenuate all frequencies above a predetermined frequency selected by the designer Frequencies below cut-off are passed without any effect 2