Shure beta 87c Output Impedance, Output Clipping Level, Maximum SPL, Self-Noise, Dynamic Range

MODEL BETA 87C CONDENSER MICROPHONE Specification Sheet

Output Impedance

Rated at 150 ohms (100 ohms actual ±20%) Recommended minimum load impedance: 800 ohms

Sensitivity (at 1,000 Hz)

Open Circuit Voltage . . . . . . . . . . . . . . . . –51 dBV/Pa (2 mV) (1 Pa = 94 dB SPL)

Output Clipping Level	–6 dBV (0.5 V)
1000 ohm Load at 1,000 Hz
Maximum SPL

139 dB at 1,000 Hz (0.25% THD, 1000 ohm load)

Self-Noise

22 dB typical, A-weighted

24 dB typical, weighted per DIN 45 405

(equivalent sound pressure level; measured with true rms voltme- ter)

Dynamic Range

117 dB (maximum SPL to A-weighted noise level)

Hum Sensitivity

–5 dB equivalent SPL, maximum, in a 1 mOe field (60 Hz)

Signal-to-Noise Ratio

72 dB at 94 dB SPL (IEC 651)*

*S/N ratio is difference between 94 dB SPL and equivalent SPL of self–noise A-weighted.

Polarity

Positive pressure on diaphragm produces positive voltage on pin 2 relative to pin 3 of the output connector. See Figure 4.

BETA 87C BLOCK DIAGRAM

FURNISHED ACCESSORIES

Swivel Adapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A25D

REPLACEMENT PARTS

Grille . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . RK312

OPTIONAL ACCESSORIES

Phantom Power Supply . . . . . . . . . . . . . . . . . . . . . . PS1A Isolation Mount . . . . . . . . . . . . . . . . . . . . . A53M, A53HM

Power

Phantom Supply Requirement . . . . . 11 to 52 Vdc, positive at both pins 2 and 3 Current Drain . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.0 to 1.2 mA

Connector

Three–pin (XLR) professional audio

Case

Aluminum construction with painted blue metallic finish, and hardened steel grille with nickel satin chrome plating

Dimensions

See Figure 5

192mm

(7–9/16in.)

21 mm	51 mm
(53/ in.)	(2 in.)
64

OVERALL DIMENSIONS

Net Weight

Net: 207 grams (7.6 oz)

Packaged: 565 grams (1.24 lbs)

Environmental Conditions

Operating: –18°to 60° C (0° to 135° F)(relative humidity <90%)

Storage: –29°to 74° C (–20°to 165° F) (relative humidity <80%)

Carrying/Storage Bag . . . . . . . . . . . . . . . . . . . . . . . 26A13

Replacement Amplifier Assembly . . . . . . . . . 90KF2600

Windscreen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A85WS 7.6 m (25 ft.) Cable . . . . . . . . . . . . . . . . . . . . . . . . . . C25F

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