Neumann U47 Large Diaphragm Tube Condenser Microphone serial# 4341.
Includes original carbon box, power supply, microphone mount and Pelican case for entire setup. The original U 47, invented in 1947, was the first switchable pattern condenser microphone. It has become the most revered vocal microphone in history, and inspired dozens of attempts to recreate its sound.
The U 47 could produce either a Cardioid or Omnidirectional pickup pattern. The pattern switch was located on the microphone body, and worked by disabling the polarization voltage to the rear diaphragm.
U 47(The U 48, introduced around 1957, was a U 47 that provided either Cardioid or Figure-of-8 patterns. The only difference between Omni and Figure-of-8 patterns is the polarity of the rear capsule.)
The U-47 did not maintain equal output levels across patterns. This is a characteristic that Neumann engineers sought to improve in later mics, such as the M 49. The U-47’s output was 5dB hotter in Cardioid mode than in Omni, because the capsule’s rear diaphragm was simply disconnected in Cardioid mode, avoiding the capacitance losses of having it in the circuit. See the history of the M49 for more information.
The original U47 employed a Telefunken VF14 tube, which would become hard to find within a few years, leading to changes to the U47 design as well as the introduction of the U47fet, a FET condenser intended to sound the same as its tube-amplified sibling.
Early U47 (and U48) mics contained Neumann’s M7 capsule, in which the brass backplate was covered with a thin PVC diaphragm. PVC ages poorly, and as early as 1958 the Neumann factory was using the M7’s successor, a capsule known as the K47/49, which used a metallized polyester diaphragm.
The K47 capsule used a single, shared backplate, which caused tensioning challenges, in that both diaphragms would have to be tuned identically to produce balanced Figure-of-8 or Omni patterns.
Tech Notes: Original componets, impedance set to 200 ohm. all original components in PSU in original carbon box (with serial) capsule ok but might need re-skin. Turned capsule over. incredibly quiet VF14M s/n333 Slightly tarnished microphone body. Sounds full and creamy, original capsule.