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Quad Oddity
A History Of Neumann's QM69
By Jeff Calder

MIX MAGAZINE/December, 1994

The Neumann QM69 was developed in 1972 to accommodate the anticipated demand for quadraphonic recording. The QM69 was essentially a modification of the SM69, Neumann's classic stereo microphone. Although stereo recording methods had been developed in England as early as 1931, the first commercially available "coincidental" stereo mic was the Neumann SM2, introduced in 1957. A small capsule mic, the SM2 was replaced by the more flexible SM69 tube model, evolving into a solid-state instrument by the early 70's.

When Neumann leapt into the quad fray, designer Gerhardt Bore simply converted the SM69's two-times variable pattern to four cardioid capsules and created the four-in-one QM69. The QM69 is a four times cardioid version of the SM69, with four seperate amplifiers. Its two U67 dual-membrane condenser capsules are arranged with a rotatable upper pair above a stationary lower pair. Each head-grille is color-coded(green/red/yellow/blue) and assigned the following dirctions:  left back, right front, left front, right back. The QM69 has the same power supply (NQ69) as an SM69 with two additional outputs.

According to Jerry Graham, an unnoficial Neumann historian, the original QM69 had the  SM69-like head-grille mounted on a bar from which two SM69-style bodies descended, forming a "pi" shape. Graham states that only 50 of those double-body mics were manufactured the first year. After that, the QM69 became the more conventional single-body mic pictured here.  Neumann literature described the QM69's directional diagram as a "cloverleaf," though it's perhaps better described as four times cardioid. It noted the mic's capability to capture "4-channel information without any arrival time differences." In other words, The QM69 could circumvent the phasing problems associated with multiple mics placed in close proximity. "It was perfectly mono-compatible," according to Jerry Graham.

The QM69 was discontinued in December 1982, a decade after quad went poof, Neumann didn't stock-pile them--they were made to order--so few are around today. With the exception of the KU80 binaural head mic, the QM69 was the most expensive Neumann of the early 70's, listing for $1,350. (By comparason, the SM69 was $1,158, and a U87 just $495.)  At the time of its demise, the QM69 listed for $3,147, and of course, today the quad oddity can fetch a high price on the vintage mic market.

The QM69 can be found in a number on contemporary applications.  Peter Hubner, cheif engineer at the Ambasador Auditorium on Pasadena, California, uses the QM69 for live radio and television broadcasts of classical and jazz events. And at Southern Tracks Recording in Atlanta, the QM69 has been used as a stereo mic for piano--an ambient and overhead mic utilizing its 4-output capability--and at a recent session for The Swimming Pool Q's involving ten kilted Scottish bagpipers marching around the studio perimeter.

So quad may be a dead issue, but there's still life in this classic mic!