Shure A15HP High Pass Filter

The Shure A15HP is a balanced in-line high pass filter in an XLR barrel that rolls off audio below 100 Hz to reduce 60 Hz electrical hum, low-frequency wind noise, air-conditioner rumble, and stand-transmitted vibration. Into a low-impedance microphone input of 800 ohms or more it delivers a 12 dB per octave rolloff below 100 Hz, with flat response above the knee and a maximum insertion loss of 0.5 dB at 1 kHz.