Shure SM81-LC Unidirectional Condenser Instrument Microphone Designed For Studio Recording & Broadcasting

SM81-LC - Overview

• 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:

  • Type: Condenser (electret bias)
    
    
  • Frequency Response: 20 to 20,000 Hz
    
    
  • Polar Pattern: Cardioid (unidirectional) response-uniform with frequency, symmetrical about axis
    
    
  • Output Impedance: Rated at 150 ohms (85 ohms actual)
    Recommended minimum load impedance: 800 ohms (May be used with loads as low as 150 ohms with reduced clipping level)
    
    
  • Output Configuration and Connector: Balanced, transformer-coupled output; male XLR connector
    
    
  • Sensitivity (at 1,000 Hz): Open Circuit Voltage: -45 dBV/Pascal (5.6 mV (1 Pascal = 94 dB SPL)
    
    
  • Clipping Level (at 1,000 Hz): 800 ohm Load:
    -4 dBV (0.63 V)
    150 ohm Load: -15 dBV (0.18 V)
    
    
  • Total Harmonic Distortion: Less than 0.5% (131 dB SPL at 250 Hz into 800 ohm load)
    
    
  • Maximum SPL (at 1,000 Hz):
    800 ohm load: 136 dB (attenuator at 0) 146 dB (attenuator at -10)
    150 ohm load: 128 dB (attenuator at 0) 138 dB (attenuator at -10)
    
    
  • Hum Pickup: -3 dB equivalent SPL in a 1 mOe field (60 Hz)
    
    
  • Self-Noise (equivalent sound pressure levels; measured with true rms voltmeter):
    16 dB typical, A-weighted
    19 dB typical, weighted per DIN 45 405
    
    
  • Signal-to-Noise Ratio: 78 dB (IEC 651)* at 94 dB SPL
    *S/N ratio is difference between 94 dB 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; -6 dB/octave below 100 Hz; -18 dB/octave below 80 Hz
    
    
  • Attenuator Switch Positions (Lockable): 0 or -10 dB
    
    
  • Power: Supply Voltage: 11 to 52 Vdc, positive, pins 2 and 3
    Current Drain: 1.2 mA max.
    
    
  • Environmental Conditions:
    
    Temperature:
  • Storage: -29 degrees to 74 degrees C (-20 degrees to 165 degrees F)
  • Operating: -6.7 degrees to 49 degrees C (20 degrees to 120 degrees F)
    
    Humidity:
  • Storage 0 to 95% relative humidity at room temperature (72 degrees to 80 degrees F, 22 degrees to 27 degrees C)
    
    
  • Case: Steel construction with vinyl metallic paint finish and stainless steel screens
    
    
  • Weight:
    Net: 230 grams (8 oz)
    Packaged: 740 grams (1 lb 10 oz)
   

• GTIN:

  0042406051194