Vintage original Neumann U47FET large diaphragm 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.
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 States:
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].
Tech Notes: All original components, repaired dry joint, cleaned switches.microphone in really good condition both aesthetically and electronically. Extremely low noise floor, full bodied and round sound, yet very dynamic. Ideal microphone for out kick drum, brass, upright bass and guitar cabinets.