Condenser mic is a microphone type that uses a charged capacitor to capture sound with high sensitivity.
Technical Details
The capsule construction consists of a 6-20 µm thin plastic or metal diaphragm spaced 10-50 µm from the backplate. The polarization voltage is 48V (phantom power) or supplied via internal batteries. Electret condenser microphones use a permanently charged plastic film and only require 1.5-9V operating voltage. Large-diaphragm microphones (diameter >25mm) offer higher sensitivity, while small-diaphragm versions (<20mm) provide more precise transient response. Typical sensitivity values range from -37 to -32 dBV/Pa.
History & Development
Edward Christopher Wente developed the first condenser microphone for telephone applications at Bell Laboratories in 1916. Georg Neumann introduced the first studio condenser microphone, the CMV 3, in 1928. In 1962, the electret principle developed by Gerhard Sessler and James West revolutionized the technology by eliminating the need for external polarization. The Neumann U 47 (1947-1965) shaped film sound in the 1950s, followed by the AKG C 414 (1971) as a standard for dialogue recording.
Practical Application in Film
Condenser microphones dominate professional film productions due to their detailed resolution. The Schoeps CMIT 5U serves as a shotgun mic standard for boom operation on exterior shoots, while the Neumann TLM 103 is prominent for studio ADR recording. "Dunkirk" (2017) used waterproof DPA condenser microphones for underwater scenes. Lavalier condenser microphones, such as the DPA 4061, remain nearly invisible with a 4mm diameter. Their high transient accuracy captures explosions and combat scenes without distortion up to 140 dB SPL.
Comparison & Alternatives
Compared to dynamic microphones, condenser microphones offer 10-20 dB higher sensitivity and an extended frequency response, but they require a power supply and are more sensitive to humidity. Ribbon microphones surpass them in natural sound reproduction but only achieve -50 dBV/Pa sensitivity. Modern alternatives like the Rode VideoMic Pro Plus combine internal batteries with USB-C charging for wireless applications. In budget productions under €100,000, electret microphones often replace expensive studio condensers with 80% of the sound quality.