Western Electric 639 is sort of a hybrid microphone, since it has both a dynamic moving coil and a ribbon element. It used the 630A omni-directional dynamic unit with the addition of a crimpled bi-directional assembly. There were two versions, the 639A and the 639B. The 639A came with 3 switchable settings while the 639B include 3 additional cardiod settings .
639A and 639B
- R – figure of eight (ribbon/bi-directional)
- D – non-directional (dynamic/omin-directional)
- C – cardiod (combined pattern)
639B’s additional settings
- 1 – cardiod with little rear sensitivity
- 2 – cardiod with moderate rear sensitivity
- 3 – cardiod with heavy rear sensitivity
The microphones were designed by the Bell Telephone Laboratories, but the actual manufacturing was by the Western Electric Company. They were released in 1939 thus the 39 in the name. The microphones initially carried the Western Electric branding and sometime in 1941 it was changed to Altec, the audio spin-off of Western Electric.).
The microphones have a unique 3 pin setup. rather than a XLR 3 pin triangular pattern, the pins are all in a straight line. To solve the problem on playing these today, you need to find an adapter that converts the 3 pins to an XLR. Front End Audio carries the Coles 4069 adapter which convert the old Western Electric / Altec connectors to XLR.
The 639 microphone was nicknamed the Birdcage mic because of it’s size and how it resembles a birdcage. Since the microphone was a combo mic and as a result it made it quite heavy, weighing in at 3.5 lbs. It dimensions are approximately 7.5 x 4.5 x 3.5 inches.
Rather that have a really lengthy article on the Western Electric 639, I thought I would include a fantastic link to a great website called Coutant.org and their article on the Altec 639.
These microphones are pricy on Ebay. They typically sell for $500 or more. The ones that are in really good condition can sell for as much as $1200-$1500. Often you will see otherwise nice 639’s with missing or broken grills.