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Neumann U47 fet

Supercardioid Condenser Microphone

The 47fet was intended to be a phantom-powered, FET version of the U47 tube microphone, designed a few years after the VF14 tube at the heart of the U47 became unavailable.

Like the U 47, the fet model used Neumann’s K47 capsule, variously referred to as the K 47, K 47/49 and K 47fet. (Read more about the K47/K49 capsule.)

This is a dual-diaphragm, large diaphragm (34mm OD) capsule with a single, shared backplate and center-terminated 6-micron Mylar diaphragms. Because the U47 Fet was a fixed Cardioid microphone, Neumann used K47 capsules (designed “K47Fet”) whose rear sides did not meet specifications for use in multipattern mics. Therefore, unlike a multipattern K47 mic, a dirty or abused U47Fet capsule cannot be rotated 180°.

The mic had a transformer-coupled output, although the design of transformer differed from the BV8 found in the tube U 47.

Oliver Archut

Aside from the ratio of the BV8 you find in the U47, the winding technique of the fet 47’s transformer differs too. The Fet47 [transformer] is more [closely] related to the BV12 you find in the U67.

There are a couple of different BV8 revisions, but all of them share the multiple-chamber winding technique, [whereas] the Fet47 [transformer] and the BV12 are just plain old mantle [transformers].

Two versions of the microphone were sold:

• U47 fet i - male XLR connector
• U47fet - male DIN 41524 (Tuchel) connector

(Each of the above was also available in a “dark matt finish,” specified U 47 fet i mt or U 47 fet mt.)

The capsule is shockmounted within the headbasket to reduce mechanical interference.

The mic was manufactured from 1969 through 1986.

U47 FET exploded view: photo courtesy Hansén Audio, Sweden

The Neumann U47 fet is also known as: 47fet, U-47-FET, fet47, U-47fet, .

The mic was released in 1969.

Specifications

Frequency Response - SupercardioidClick Graph to Compare!

Pickup Patterns	Pads & Filters
Supercardioid (8 mV/Pa; 40 - 16,000 Hz)	Pad: -10dB (Via Switch) Filter: HPF @ 200 Hz (Via Switch)

Capsule Dimensions	Impedance	SPL/Noise
Capsule diameter: 34mm	150 Ohms (Low)

Weight	Length	Max Diameter	Interface(s)
710g (25.04oz)	160mm (6.30'')	63mm (2.48'')	3-pin XLR male (1)

Power Specifications
Requires phantom power Phantom voltage: 48v

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