The Shure Beta 91a was designed to be used with gruesy, as well as with other low-frequency tools, including the piano. Characterized by an updated microphone capsule, integrated preamplifier and XLR connection, the Beta 91a offers a strong response to low frequencies and combines upper and punch connection for a studio sound, even at extremely high levels of sound pressure (SPL).

• Type: Capacitor
• Frequency response: 20 - 20,000 Hz
• Polar Pattern: Seeds-Cardioid (cardioid in the hemisphere above the assembly surface)
• Impedance: 146 ohm
• Sensitivity (a 1 KHZ, open circuit voltage): - 48.5 DBV / PA (3.8mV), 1 PASCAL = 94 DB SPL
• Maximum SPL (1 khz a 1% THD): Load of 1000 ohm => 151 dB, load of 2500 ohm => 155 dB
• S / N report (referring to 94 DB SPL a 1 kHz): 64 dB
• Dynamic range (a 1 kHz): 1000 ohm load => 121.5 dB, load of 2500 ohm => 125.5 dB
• Common Mode Rejection (20 Hz at 20 kHz): > 55 dB
• Clipping Level (20 Hz-20 kHz a 1% THD): Load of 1000 ohm => 7.50 DBV, 2500 ohm => 12.5 DBV, self noise (typical, SPL equivalent to-Weighted): 29.5 dB SPL-To
• Polarit: A positive pressure on the diaphragm produces a positive voltage on the foot 2 compared to the foot 3
• Weight: 480 g