Up for sale, a mid 1960s Sony C-37A tube condenser microphone in near-mint condition and in perfect working order, complete with the original case, CP-3B power supply, cables, and user manual. A true time capsule find that recently surfaced, this C-37A is completely original, never necessitating any maintenance, and recently benefitting from a thorough battery of tests to ensure optimal functionality and an ideal noise floor.
This iconic large-diaphragm multi-pattern tube condenser was first introduced in Japan in 1955 (making its way to America in ‘58), and quickly found widespread usage throughout the Wrecking Crew era of the ‘60s at the studios of major Hollywood labels including Capitol records, Sunset Sound, RCA, and Gold Star. The sound of the C-37A has appeared on countless classic records over the years, favored by artists including Frank Sinatra, U2, and Cannonball Adderly, among innumerable others. It functions exceptionally well as both a vocal and instrumental microphone, also excelling in a variety of non-musical applications, including extensive usage in broadcast and voice acting work by notable names like Casey Kasem and “The Man of 1,000 Voices” Mel Blanc, who recorded the voices of Bugs Bunny, Daffy Duck, and the rest of his myriad characters with a C-37A.
Responsible for the iconic “smokey” vocal sound of the ‘60s, the C-37A is a mic that almost circumvents the need for any EQing; it has a natural midrange warmth with a slight dip in the upper mids that is ideal for vocals, and the silky smooth treble response tempers any guitars or vocals that may otherwise be too harsh or bright. Despite lacking a pre-attenuation pad, the low output of the C-37A ensures that it can be used on loud sources without fear of overloading the preamp. Originally designed to compete with the Neumann U47, the C-37A sports a number of unique innovations that result in its distinctive response. The C-3 edge-terminated capsule, measuring 37mm (1.45”) in width, has a 6 micron mylar diaphragm, “sputtered” with a layer of gold 3 microns thick for ideal conductivity and temperature control. Additionally, the C-37A features a tuned acoustic baffle chamber behind the capsule that can mechanically alter the polar pattern from cardioid to omni-directional with the turn of a screwdriver (accessed on the back of the microphone).
The CP-3B power supply unit was the fourth power supply iteration, introduced in 1964, featuring more tonal sculpting options than prior iterations. The rotary knob selects the low-frequency rolloff point (essentially a high pass filter), with four positions:
M (Music) - flat response (-2dB @ 30Hz)
M1 - rolloff 1 (-3dB @ 80Hz)
V1 (Voice) - rolloff 2 (-3bD @ 200Hz)
V2 - rolloff 3 (-3dB @ 600Hz)
The CP-3B also features a push-button High Cut On/Off switch, and two impedance and output level settings, and operating voltage is also user adjustable. The CP-3B is also notable for being the first iteration of Sony PSU to be built around a PCB.
This microphone has a low noise floor, currently fitted with a vintage RCA orange block logo 6AU6. It’s in remarkable cosmetic shape, with the only real wear on the microphone being some light peeling of the rubber on the output cable. The Olive Green finish is nigh flawless save for a few specks of wear, the grille is practically pristine, and all of the serial/model stamps are present. The CP-3B power supply is also very clean; the only wear of note is some writing at the rotary bass rolloff point knob indicating the function of the knob, written in pen by a previous owner.
The original three-compartment case is included, as well as the leather carrying case for the microphone itself. Also included is the original five-pin EC-10B cable, to connect the microphone to the power supply, and a modern three-pin output cable. Finally, the original directional pattern and frequency response diagrams (for both cardioid and omni-directional modes) are included, along with a photocopy of the original user manual.