The Shure Beta 91A is a half-cardioid condenser microphone designed for use with kick drums, as well as other traditional low-frequency applications including piano. Featuring an updated microphone capsule, integrated preamplifier, and XLR connection, Beta 91A offers a strong low-frequency response and is specifically tailored for bass frequency applications. The Beta 91A combines superior attack and punch for studio-quality sound, even at extremely high sound pressure levels (SPL).

Features

• Uniform half-cardioid polar pattern for maximum gain-before-feedback and rejection of off-axis sound
• Precision-engineered low-profile design features integrated preamplifier and XLR connector to maximize setup efficiency while minimizing stage clutter
• Frequency response tailored for kick drum/low frequency applications with a wide dynamic range for use in high SPL environments
• Two-position contour switch to maximize attack and clarity depending on application: select the flat response setting for natural sound in most applications or the “low-mid scoop” setting for a strong low frequency “punch”with plenty of higher frequency attack.
• Requires no external mounting or accessories for ease of use and storage
• Furnished with zippered pouch

Specifications

• 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): -48.5dBV/Pa (3.8mV) (1 pascal= 94dB SPL)
• Maximum SPL (1kHz a 1% THD): 1,000 Ohm load: 151dB, 2,500 Ohm load: 155dB
• Signal-to-Noise Ratio (referenced at 94dB SPL at 1kHz): 64dB
• Dynamic Range (at 1kHz): 1,000 Ohm load: 121.5 dB / 2,500 Ohm load: 125.5dB
• Common Mode Rejection (20Hz to 20kHz): >55dB
• Clipping Level (20Hz – 20kHz at 1% THD): 1,000 Ohm Load: 7.50dBV/ 2,500 Ohm load: 12.5dBV
• Self Noise (Typical, equivalent SPL, A-weighted): 29.5 dB SPL-A
• Polarity: Positive pressure on diaphragm produces positive voltage on pin 2 with respect to pin 3
• Weight: Net: 470g (16.6oz)
• Frequency Contour Switch: 7dB of attenuation centered at 400kHz
• Connector: Three-pin professional audio (XLR), male, balanced
• Power Requirements: 11-52 Vdc phantom power, 5.6mA