The Neumann Model QM 69
Quadro condenser microphone.
The Model SM 69 is down the page.
With the QM 69 in 1974, the firm also made a brief excursion into the realm of quadraphony. As Neumann employee Ernst Weiℜ remembers: I don’t think that Georg Neumann ever said, “Now we must build a quadraphonic microphone.” I expect a few people specifically requested one, so we took an SM 69 and inserted not two but four amplifiers into the shaft and gave all four capsules a cardioid polar pattern. Neumann has had very few flops over the years, but the quadraphonic microphone was certainly one of them.
Quoted from Neumann the Microphone Company, p. 92
The following five photos are provided by Justin.
The Neumann QM 69 was developed in 1972 to accommodate the anticipated demand for quadraphonic recording. The QM 69 was essentially a modification of the SM 69, 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 SM 2, introduced in 1957. A small capsule mic, the SM 2 was replaced by the more flexible SM 69 tube model, evolving into a solid-state instrument by the early seventies.
When Neumann leapt into the quad fray, designer Gerhardt Bore simply converted the SM 69’s two-times variable pattern to four cardioid capsules and created the four-in-one QM 69. The QM 69 is a four times cardioid version of the SM 69, with four separate amplifiers. Its two U 67 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 directions: left back, right front, left front, right back. The QM 69 has the same power supply (NQ 69) as an SM 69 with two additional outputs.
According to Jerry Graham, an unofficial Neumann historian, the original QM 69 had the SM 69-like head grille mounted on a bar from which two SM 69-style bodies descended, forming a “pi” shape. Graham states that only 50 of these double-body mics were manufactured the first year. After that, the QM 69 became the more conventional single-body mic pictured here.
Neumann literature described the QM 69’s directional diagram as “cloverleaf,” though it’s perhaps better described as four times cardioid. It noted the mic’s capability to capture “four-channel information without any arrival time differences.” In other words, The QM 69 could circumvent the phasing problems associated with multiple mics placed in close proximity. “it was perfectly mono-compatible,” according to Jerry Graham.
The QM 69 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 KU 80 binaural head mic, the QM 69 was the most expensive Neumann of the early seventies, listing for $1,350. (By comparison, the SM 69 was $1,158, and a U 87 just $495.) At the time of its demise, the QM 69 listed for $3,147, and, of course, today the quad oddity can fetch a high price on the vintage mic market.
The QM 69 can be found in a number of contemporary applications. Peter Hubner, chief engineer at the Ambassador Auditorium in Pasadena, Calif., uses the QM 69 for live radio and television broadcasts of classical and jazz events. And at Southern Tracks Recording in Atlanta, the QM 69 has been used as a stereo mic for piano—an ambient and overhead mic utilizing its four-output capability—and at a recent session for Swimming Pool Q 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!
Reprinted from Mix Magazine, December 1994
Download the specifications for the QM 69.
(in German)
The Neumann Model SM 69
stereophonic condenser microphone
In 1964 Neumann introduced the SM 69, which featured two large-diaphragm capsules from the U 67. The principle of rotatable capsules was retained, as was the AC701 tube. This, however, was replaced by solid-state circuitry for the SM 69 FET.
In 1979 came the USM 69 switchable stereo microphone that is still in the Neumann catalog today. It accepts phantom power and is switchable at the microphone.
Quoted from Neumann the Microphone Company, p. 92
Detail view of the stand mount.
Download the specifications for the SM 69.
(in English)
