The Beta 91A is a half cardioid condenser boundary microphone. You can expect a strong low end response as it is specifically tailored for bass frequency applications, and 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 maximise setup efficiency while minimising 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 maximise 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

Specifications:

• Transducer Type : Condenser
• Polar Pattern: Halfcardioid
• Frequency Response: 20 Hz - 20 kHz
• Sensitivity (1 kHz): -48,5 dBV/Pa / 3,8 mV/Pa
• Equivalent Selfnoise:

  25,5 dB(A)

• Sound Pressure:

  155 dB

• Weight: 470 g

Manufacturer: Shure