The M 269 is a large-diaphragm, multipattern tube condenser
microphone. It is a variation of the Neumann U-67,
Neumann developed the M269 by making the following changes
to the basic U-67 design:
The EF86 was swapped for an AC701 (aka AC701k) triode vacuum
The “Omni” and “Figure 8” positions on the pattern selection
switch below the headbasket are replaced by a remote-control feature labelled
unlike the U67, provides continuously-variable pattern selection.
RF shielding was incorporated into the M269 plug.
.The K67 was Neumann’s first capsule with dual backplates.
Its famous predecessor, the K47 capsule, employs a single, “shared” backplate,
which proved too difficult to tune for symmetrical figure-of-8 response. The
use of two backplates allowed technicians to tune the two diaphragms separately
and equally before joining them into a single, completed capsule.
A special circuit within the amplifier distinctly attenuates
all frequencies below 30[Hz], while those above 40[Hz] are reproduced linearly.
The microphone amplifier’s response may be extended to below 20[Hz] flat by
opening the jumper “S-2” in the amplifier itself.