Neumann U47 FETi

From Sound-on-Sound magazine, July 2015

"The U47 FET was conceived in 1969, the driving impetus being that Telefunken had stopped production of the VF14 valve that was employed as the impedance converter in the original U47 microphone. With the rapid advances being made in the late 1960s in the quality and capability of silicon transistors, Neumann decided to re–engineer the U47 as a solid–state, single-pattern microphone, using the recently perfected field–effect transistor (FET) to provide the high–impedance interface with the capsule. The resulting microphone, which entered mainstream production in early 1972, was called the U47 FET, although it is often referred to simply as the ‘fet47’."

Neumann released an anniversary edition of the U47 Fet in 2015.

Technical Specification:

• Directional pattern: hypercardioid
• Acoustical operating principle: pressure gradient transducer
• Frequency range: 40 to 16000 Hz
• Sensitivity: 8 mV/Pa
• EIA rating G_M : - 133 dBm
• Output impedance: 150 Ohm balanced ond floating
• Max. SPL for less than 0,5 % THD: 148 dB
• Total dynamic range of the microphone amplifier: 130 dB ^.
• Power requirement: 48 V DC (+6/-8V); 0.5 mA
• Output connector: Amphenol Tuchel NT 3262 or Switchcraft A3M 3-pin
• Microphone Stand Threod: 5/8" 27 tpi
• Weight: 24.6 ozs. (695 g)
• Dimensions : dia. 2 l/2"; length 6 1/4"

Technical manual for the U47 Fet, published in 1974

A post about the U47 Fet at the Coutant website.

Sound on Sound magazine on the U47 Fet, and its re-release in 2015.