U 67

Common name: Neumann U 67

Production Status: Discontinued / Vintage

The U 67 replaced the U 47 in Neumann’s line. The prototype series was called U 60 because it was made available from 1960, the year in which the prototypes were sent for testing to selected recording studios. It was then renamed U 67 to honor its predecessor. All the experience gathered by professional users with the previous microphones was taken into account when Neumann designed and engineered the U 67. The microphone has three switchable patterns: omnidirectional, cardioid and bidirectional. It features a switchable capacitive attenuator circuit (-14 dB in the first version and -10 dB later on) and a high pass filter to compensate for proximity effect when the capsule is set to cardioid or bidirectional,  working as a pressure gradient transducer. The “roll off” filter also works for the omnidirectional pattern if needed. The new capsule named K 67 features MCF gold layered diaphragms and exhibits better polar pattern response compared to the previous M7, becoming hyper-cardioid at high frequencies and producing a much more accurate bidirectional pattern. The K 67 capsule has two separate back electrodes and it is made of two halves, this allows for near-perfect matching and achieves the finest bidirectional pattern. The head grille shape derives from the M 49 grille, which had been designed and developed with NWDR – Nordwestdeutscher Rundfunk (Northwest German Broadcasting) to minimise the sound imprint of the cylindrical grille (refer to Stephen Paul’s piece about the effect of the U 47 head grille). The new microphone preamplifier was designed around an easily available high-performance vacuum tube. The chosen tube was the EF 86, a pentode working as a triode in an anode amplifier configuration. The preamplifier has a high-frequency emphasis and de-emphasis circuit to minimize tube noise and avoid the need for special tube selection. The Bv.12 output transformer has separate feedback windings to minimize overall distortion. Its design minimizes hum and provides better impedance matching with the coupled microphone preamplifier. The microphone can be easily disassembled without tools while humidity-sensitive high-impedance components are insulated. The microphone was produced from 1960 to 1971. In 1993 a revival limited edition was manufactured (less than 400 pieces). Recently Georg Neumann GmbH started to manufacture the U 67 again. According to Neumann, it is “meticulously reproduced to original specifications”. The reissued model shares common mechanical parts with the U 87Ai. The U67 microphone has a unique smooth sound.
For more information, read Micpedia’s article on the U 67.