The Shure SM81 is a high-quality unidirectional condenser microphone designed for studio recording broadcasting and sound reinforcement. Its wide frequency response low noise characteristics and low RF susceptibility have made it a standard for applications involving acoustic instruments especially guitar piano and cymbals.

SM81-LC - With windscreen no cable. Phantom power required.

The SM81 is ruggedly constructed. It operates on phantom power and performs over a wide range of temperatures and humidity conditions. It is furnished with a swivel adapter attenuator-switch lock foam windscreen and case for carrying and storage. Other accessories are available.

Features:

•0 Hz to 20 kHz frequency response
•Flat response curve for accurate reproduction of sound sources
•Low noise and high output clipping level
•Low distortion over a wide range of load impedances
•Cardioid polar pattern uniform with frequency and symmetric about axis providing maximum rejection and minimum coloration of off-axis sounds
•Low RF susceptibility
•Selectable low-frequency response: flat 6 or 18 dB/octave rolloff
•0 dB/10 dB lockable attenuator switch
•Phantom powering (DIN 45 596 voltages of 12 to 48 Vdc)
•Rugged steel construction for durability
•Field-usable over wide range of temperature and humidity conditions

SPECIFICATIONS

SM81 Condenser Mic

• Type: Condenser (electret bias)
• Frequency Response: 20 to 20,000Hz
• Polar Pattern: Cardioid (unidirectional) response-uniform with frequency, symmetrical about axis
• Output Impedance: Rated at 150? (85? actual)
• Recommended minimum load impedance: 800? (May be used with loads as low as 150? with reduced clipping level)
• Output Configuration and Connector: Balanced, transformer-coupLED output; male XLR connector
• Sensitivity (at 1,000Hz): Open Circuit Voltage: -45dBV/Pascal (5.6 mV), (1 Pascal = 94dB SPL)
• Clipping Level (at 1,000Hz): 800? Load: -4dBV (0.63 V), 150? Load: -15dBV (0.18 V)
• Total Harmonic Distortion: Less than 0.5% (131dB SPL at 250Hz into 800? load)
• Maximum SPL: (at 1,000Hz): 800? load: 136dB (attenuator at 0) 146dB (attenuator at -10), 150? load: 128dB (attenuator at 0) 138dB (attenuator at -10)
• Hum Pickup: -3dB equivalent SPL in a 1 mOe field (60Hz)
• Self-Noise (equivalent sound pressure levels; measured with true rms voltmeter) 16dB typical, A-weighted, 19dB typical, weighted per DIN 45 405
• Signal-to-Noise Ratio: 78dB (IEC 651)* at 94dB SPL, *S/N ratio is difference between 94dB SPL and product's equivalent self noise (SPL A-weighted)
• Overvoltage and Reverse Polarity Protection: Max. external voltage applied to pins 2 and 3 with respect to pin 1: +52 VDC, Reverse polarity protection: 200 mA max. (diode-clamped)
• Polarity: Positive pressure on diaphragm produces positive voltage on pin 2 relative to pin 3
• Cartridge Capacitance: 54 pF
• Low Frequency Response Switch Positions: Flat; -6dB/octave below 100Hz; -18dB/octave below 80Hz
• Attenuator Switch Positions (Lockable): 0 or -10dB
• Power: Supply Voltage: 11 to 52 VDC, positive, pins 2 and 3, Current Drain: 1.2 mA max
• Environmental Conditions:
• Temperature:
• Storage: -29?