Use the A15AS with any low-impedance microphone, including phantom-powered condenser microphones, such as the Shure SM81. It can be used in line between the microphone and its power supply. (This model is not suitable for use with the condenser powering system called "A-B Powering.")
The A15AS attenuator bridges the microphone output and allows maximum signal handling with a minimum of loading-caused distortion or reduction in clipping level.
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