The C391 B high-performance small-diaphragm condenser microphone is a combination of the Blue Line Series CK91 and the SE300 pre-amplifier. The microphone has a cardioid polar pattern, a low self-noise and very good transient response for a bright and brilliant sound. It also features the ability to quickly interchange its capsule with one of the other capsules of the Blue Line Series, making it an excellent mic for demanding broadcast applications. The C391 B provides a switchable bass roll-off/attenuator with three positions: flat, 75Hz and 10db attenuation.

General Specifications

  • Polar Pattern Cardioid
  • Audio frequency bandwidth 20 - 20000 Hz
  • Equivalent noise level 17 dB-A
  • Sensitivity 10 mV/Pa
  • Signal to Noise 77 dB-A
  • Preattenuation Pad 10 dB
  • Bass cut filter 75 Hz
  • Recommended load impedance 1000 Ohms

Audio Output 

  • Type Balanced XLR
  • Gender Male
  • Contacts 3-pin

Powering Interface

  • Voltage 9 to 52 V
  • Current 2 mA


  • Finish dark gray


  • Height 146 mm
  • Diameter 19 mm