The Neumann QM 69 is a historical quadraphonic microphone developed in the mid-1970s during the rise of quadraphonic sound among hi-fi enthusiasts. This specialized microphone represents a variant of the SM 69 FET design with four separate outputs—one for each half of the two dual-diaphragm capsules. Engineered for professional four-channel surround sound recording, it features discrete signal paths that capture spatial audio with precise directional information. As part of Neumann's discontinued product line, it exemplifies the company's pioneering work in multichannel recording technology during the quadraphonic audio era.