Designed for touring and live-sound applications, the Crown® CM-311A is a rugged head-worn microphone with unequalled performance. It sounds like the best handheld microphones—full, clear, and distortion-free, even with the loudest singers.

The CM-311A is the latest version of the Crown’s proprietary Differoid® technology. Its cardioid pickup pattern rejects sounds from the rear, such as floor monitors. Its noise-canceling ability rejects sounds ata distance, such as instruments on stage and crowd noise. This results in the CM-311A having outstandinggain-before-feedback and isolation.

Lightweight and comfortable, the mic’s headband and boom adjust to fit any singer. An included pop filtergreatly reduces breath noise and pops. Because of the boom’s unique behind-the-ear design, it does notcover up the singer’s face.

Two models are available: CM-311A and CM-311AE. The CM-311A is powered by a 9V battery or phantom power. It has a battery belt pack with an on/off switch, a programmable mic on/off switch, and a “Mic On” LED. The CM-311AE is a pig-tail version allowing you to connect it to most wireless transmitters.

NOTE: Putting an XLR connector on the CM-311AE and connecting to a mic input with phantom power WILL damage the mic element. For wired applications, use the CM-311A.

Features:

• Full, clear, distortion-free sound
• Outstanding gain-before-feedback and isolation
• CM-311A has battery/phantom belt pack
• CM-311AE connects to most wireless transmitters

Specifications:

• Transducer type: Electret condenser.
• Frequency response (typical): 50 Hz to 17,000 Hz
• Polar pattern: Cardioid
• Impedance: CM-311A, 75 ohms balanced. CM-311AE, 6 kilohms unbalanced.
• Recommended load impedance: CM-311A, 1000 ohms or greater. CM-311AE, 10 kilohms.
• Open-circuit sensitivity, typical, close-talking: CM-311A, 4 mV/Pa* (–48 dB re 1V/Pa), CM-311AE, 1.25 mV/Pa (–58 dB re 1V/Pa).
• Power sensitivity, typical, close-talking: CM-311A: –42.5 dB re 1 mW/Pa*, CM-311AE: –71.5 dB re 1 mW/Pa.
• Equivalent noise level (self noise): 26 dB SPL typical (0 dB = 0.0002 dyne/cm2), A-weighted.
• S/N ratio: 68 dB at 94 dB SPL.
• Maximum SPL: CM-311A, 148 dB SPL produces 3% THD. CM-311AE, 140 dB SPL with 3V DC, 148 dBSPL with 9V DC.
• Operating voltage: CM-311A, 9V DC internal alkaline battery or 18-48V phantom power. CM-311AE,3–9V DC from the transmitter’s battery.
• Polarity: Positive pressure on diaphragm produces positive voltage on CM-311A XLR pin 2 with respect to pin 3, and on CM-311AE shield with respect to white lead.
• Current drain: CM-311A, 6.5 mA nominal. CM-311AE, 0.27 mA nominal.
• Battery life: CM-311A, 85 hours. CM-311AE, approximately equal to transmitter battery life.
• Off-attenuation: 70 dB.
• Output connectors: CM-311A, 3-pin pro audio (XLR type). CM-311AE, supply your own to match yourtransmitter.
• Cables:
  • CM-311A: 2-conductor shielded, unbalanced cable, 42-inches (106.68 cm) from headband tobattery pack. Use 2-conductor shielded mic cable (not included) between XLR connector and mixermic input.
  • CM-311AE: In-line with this cable is a small circuit module that equalizes the microphone signal. Cable is 42-inches (106.68 cm) long from headband to module, 12-inches (30.48 cm) from module to cable end. 2-conductor shielded unbalanced cable, unterminated.
• Materials: High-impact plastic mic housing, brass boom, steel wire headband, high-impact plastic andsteel battery pack.
• Finish: Satin black.
• Net weight: Head-worn mic, 2.1 oz (61 g). CM-311A belt pack and battery, 6.1 oz (173g).
• Dimensions: Headband 5.5-in. (13.97 cm) diameter, adjustable. Boom approximately 7 in. (17.78 cm) x3 in. (7.62 cm).
• Included accessories: Microphone carrying case, WS-6 foam pop filter, clothing clip.
• Optional accessories: PH-1A phantom power supply (1 channel, AC-adapter powered). WS-14 accessorywindscreen.

*: 1 pascal = 10 dynes/cm2 = 10 microbars = 94 dB SPL.