Neumann M7 microphone capsule, 1947-present.

Neumann developed the double-membrane capsule with a shared backplate using an idea patented by Braunmuhl and Weber in Germany in 1927. In this backplate were 153 precisely hand-drilled and critically placed holes, some of which went through to the opposite side. A cancellation of sound reaching the rear of the capsule was produced, resulting in a cardioid pattern. This capsule was designated the M7.

The so-called “bottle” condenser, with its M7 capsule, became the first cardioid microphone. The M7 capsule design has been in continuous production from its inception to the present. This one works with the CMV563 preamp.