neumann.berlin
the microphone company
U 67 - The Workhorse
The news came as a shock to Neumann at the end of the
1950s, when the German electronics firm Telefunken told
Neumann, that because it was the only remaining buyer of
its steel tube VF 14 M, further production of the tube was
no longer profitable for the company. After one last lot was
produced, the volume of which Neumann could decide,
the tube’s production ceased forever. With this announce-
ment the end of the world-renowned Neumann U 47 mi-
crophone drew near.
At a time, when thousands of U 47 were in use worldwide,
Neumann began to intensify its development of a succes-
sor. The company had already been producing the KM 56
miniature microphone for a few years. That microphone fea-
tured selection of all three major directional patterns: omni
directional, cardioid and figure-eight. Neumann wanted its
new model at least to have these switchable functions.
As for directionality, the legendary Neumann M 7 capsule
made it relatively simple to realize both the cardioid and
omni directional pickup patterns. However, an exact figure-
eight characteristic posed more of a challenge, because the
dual diaphragm in the M 7 shares a common central elec-
trode. The accuracy of a bi-directional pickup depends on
the precise correlation of the two capsule halves. This prob-
lem led to the development of a similar dual capsule, but
with two separate back electrodes. In addition to the abili-
ty to match the two halves exactly, it also become possible
for this capsule to respond optimally for all three patterns.
The result is the K 67 capsule, scheduled to be employed
in the successor to the U 47.
In the 1950s, it had be-
come fashionable for many
popular vocalists to sing al-
most directly into the mi-
crophone. This practice
produces a noticeable in-
crease in low frequency
response due to the so
called proximity effect.
Through this, the voice
gains volume at low fre-
quencies and sounds full-
er. Too much bass,
though, can be a problem, and to counter it, a switchable
circuit was designed to „roll-off“ low frequencies.
A switch located on the microphone head permits chang-
ing the low frequency attenuation to become effective at
100 Hz for proximity compensation. The EF 86 tube op-
erates as triode in an anode amplifier configuration into an
output transformer with separate feedback windings. The
output transformer’s special construction helps to eliminate
hum and allows internal impedance matching with the fol-
lowing preamplifier.
Finally, in 1960,
the new micro-
phone was born,
which ultimately
matured to be-
come the Neu-
mann U 67. Its
form is a variation
of the typical
cone-shaped mi-
crophone. It can
easily be disas-
sembled without
tools and incorpo-
rates all the above
mentioned fea-
tures. The proto-
type series was re-
leased as the U
60 to select re-
cording studios for
testing. It was re-
named U 67 with
the start of its
market introduc-
tion, to honor its
renowned prede-
cessor and provid-
ing continuity
with the U 47.
The U 67 quickly
gained a reputa-
tion for its unprec-
edented versatili-
ty, making it the
ideal microphone
for universal appli-
cations. The Neu-
mann U 67 be-
came known as a
true workhorse for
professional re-
cording studios everywhere. Several thousand were sold in
the first five years of its production, and as the U 67 gained
in popularity, the U 47 declined.
An era ended when the last U 47 was delivered in 1965,
with the U 67 having taken the market by storm and firmly
established as the legitimate successor. Especially in the
US, this microphone had become so well known that our
sales reps there were able to release an effective ad with
only a picture of the U 67 and the words, „ask anyone“.
The understatement was enough. Owing to its quality, ver-
satility and shape, the Neumann U 67 became the very
symbol of a high quality microphone, often imitated, but
never duplicated.
