Neumann.Berlin USM 69 i - Manual (Page 2)

he SM 69 fet and USM 69 stereo micro-
phones each have two separate dual-dia-
phragm capsules. These are mounted verti-
cally and rotate against each other. The di-
rectional polar patterns can be selected
separately for each capsule. The capsules op-
erate independently from each other.
Applications
The SM 69 fet and USM 69 condenser stereo
microphones are studio microphones for inten-
sity stereo recording. The microphones are
suitable for XY and MS recordings. The con-
struction of the capsules is the same in both
microphones. Therefore, the acoustic features
of the transducers are identical. The only dif-
ference is the method of switching the polar
patterns and the way the microphones are con-
nected to the system.
Construction
The microphone consists of the amplifier sec-
tion and the capsule head. The amplifier sec-
tion contains two microphone amplifiers op-
erating independently from each other. They
have an extremely low self noise.
Two completely separate microphone capsules
are positioned closely above each other within
the capsule head. Their diaphragms are made
out of gold-sputtered polyester film. The up-
per capsule rotates against the lower one over
a range of 270°. Color markings on the lower
capsule system help to identify the angle by
which the upper capsule has been rotated.
When sound waves reach the microphone cap-
sules from different directions they will gene-
rate audio signals with different intensity only,
but not with time differences, since the cap-
sules are in close proximity and the sound ar-
rives at both capsules simultaneously. The re-
sult is an intensity stereo signal that can be
summed together for excellent mono compa-
tibility without causing interference.
Features
• Switchable stereo microphones
• Two pressure-gradient
transducers with double
membrane capsules
• MS- or XY-stereophony
• Capsules rotary by 270°
• Very low noise
• Aperture and pick-up angles
freely choosable
• Directional characteristics
reproducably switchable,
omni, wide angle cardioid,
cardioid, hypercardioid,
figure-8