Manufacturers description

A15HP In-Line High Pass Filter
The Shure A15HP filter rolls off low audio frequencies to reduce 60 Hz electrical hum, low-frequency wind noise, air conditioner noise, or stand- and floor-transmitted low-frequency vibrations.
Features
- When loaded with a low-impedance microphone input (800 ohms or more), the rolloff is 12 decibels per octave below 100 Hz. When loaded with 150 ohms, the rolloff is 3 decibels at 100 Hz. The output is flat above the rolloff point (with a maximum loss of 0.5 decibels at 1 kHz).
Specifications
Frequency Response
Flat above rolloff point; -0.5 dB maximum at 1 kHz
Impedance
Designed for 150 ohm rated microphones and inputs
Distortion
2.5% maximum (100 mV input, open circuit output)
Connectors
Input: 3-socket XLR connector
Output: 3-pin XLR connector
Case
Full magnetic shield, steel with gray enamel finish
Dimensions
19 mm (3/4 in.) diameter; 114 mm (4 1/2 in.) long
Description
SHURE PROBLEM SOLVERS
Filters, attenuators, transformers, switches and impedance adapters to solve interface problems in installlations and in the field.