CM311

The AKG CM311 is a light, rugged head-worn mic for presenters, touring and live-sound applications, with three connector options. 

From the Manufacturer:

The CM311 reference head-worn condenser microphone is designed for touring and live-sound applications. It sounds like the best handheld microphones - full, clear and distortion-free, even with the loudest singers. Differoid stands for differential cardioid, which cancels ambient noise from floor monitors, crowds and other sources. Controlled field tests show that the Differoid provides up to 12dB more gain before feedback than conventional cardioid microphones. Many users of CM311 say that their house mix is better because the mic's isolation is nearly complete.

Features:

• Differoid noise-cancelling technology: For highest ambient noise rejection
• Cardioid polar pattern: For outstanding gain before feedback
• Condenser capsule with internal shock mount: For efficient rejection of mechanical and body noise
• Robust headband connection: For maximum comfort and freedom of movement

Specifications:

• General Specifications
  • Audio frequency bandwidth: 50 - 17000 Hz
  • Equivalent noise level: 26 dB-A
  • Sensitivity: 1.25 mV/Pa
  • Signal to Noise: 68 dB-A
  • Electrical impedance: 75 Ohms
  • Polar Pattern: Cardioid
• Dimensions
  • Length: 17.76 mm
  • Width: 13.97 mm
  • Height: 7.62 mm
  • Net Weight: 61 g
• Design
  • Finish: satin black
• Audio Output
  • Type:
    • XLR
    • mini XLR, for AKG PT's
    • W/TA4F, for use Shure bodypack transmitters.
  • Gender: Female
  • Contacts: 3-pin
• Powering Interface
  • Voltage: 18 to 48 V
• Application
  • Assisted Listening
  • Sound Reinforcement
  • Presentation
  • Retail
• Device: Headset Microphone