The Beta 91A is optimised for kick drums, as well as traditional low end applications including piano. It uses a half-cardioid condenser boundary microphone with an integrated XLR preamplifier that is tailored for a strong low-end response. It has a two-position contour switch for optimised sound signature depending on application.
Type: Electret Condenser
Frequency Response: 20Hz-20kHz
Polar Pattern: Half-cardioid (cardioid in hemisphere above mounting surface)
Impedance: 146 Ohms
Sensitivity (at 1kHz, open circuit voltage): -48.5 dBV/Pa (3.8mV)
Maximum SPL ( kHz at 1% THD): 1,000 ohm load: 151dB; 2500 Ohm load: 155dB
Signal-to-Noise Ratio (referenced at 94 dB SPL at 1kHz): 64 dB