Sony
Sony C-37A
Large-diaphragm tube condenser (6AU6 cathode follower), omni or cardioid (screw switch on the head), with the CP-3B power supply; discontinued
Approximate Some readings for this mic are uncertain; see the graphs.
Power CP-3B power supply, AC 100, 117 or 220 V, 50/60 cps, 10 VA.
- Type
- Condenser
- Pattern
- Switchable, 2
- Sensitivity
- −53 dBV/Pa
- Among 204 condensers: more output than 4%
- Among 311 mics: more output than 22%
- Rated range
- 30 – 16k Hz
- Released
- 1955
vs 75 side-address condensers
More output than 1% of 75 side-address condensers.
Each stripe is one side-address condenser with a published sensitivity, and each bar counts them; further right means more output. This mic is in blue.
Curve transparency
Instruments sources recommend it for most
Angle
Distance
Proximity effect: the bass it gains up close
From the catalog (Recording Hacks copy), p. 1. Approximate
"Uni-Directional frequency response", "Response in db", "Frequency in cps"; 0°, 90° and 180° curves. Distance, room and the low-cut setting are not stated.
Approximate: reading error up to about 1 dB.
Dashed: outside the rated range, or simulated (other angles and distances). Hover or tap the graphs for values.
In practice
All specs
| From the manual rh | ||
|---|---|---|
| Capsule | C-3 capsule, very thin plastic diaphragm sputtered with pure gold"a C-3 capsule mounted in the metal netting"; "The diaphragm of the microphone capsule is a very thin plastic film sputtered with pure gold" (p. 2). The earlier leaflet: 6 µm, gold 0.3 µm thick. | p. 2 |
| Sensitivity | −53 dBV/Pa (2.24 mV/Pa)open circuit, 250 ohm setting; ±2 dB; also −60 dBV/Pa, 50 ohm setting; also −54 dBV/Pa, omni, later spec sheet (manual-rh p. 15); also −50 dBV/Pa, cardioid, earlier leaflet (-70 dB re 1 V/dyne/cm²); omni -52. Table 4.3: open circuit voltage "-53.0" dB at 250 ohms, "-60.0" at 50 ohms, with "0 db = 1 volt/10 ubar" (10 µbar = 1 Pa); "Deviation ±2 db". The later sheet (p. 15): "Uni - 53 dB/Pa, Omni - 54 dB/Pa". The earlier leaflet's -70 and -72 dB re 1 V per dyne/cm² are converted with +20 dB. | p. 4 |
| Signal-to-noise ratio | 60 dBmore than; 1,000 cps, 10 µbar (94 dB SPL); weighting not stated; also 45 dB, earlier leaflet: more than 45 dB for 1 µbar at 1,000 c/s. "Signal to noise ratio: More than 60 db on the 1000 cps, 10 ubar sound." | |
| Output impedance | 250 ohmswitchable 50 or 250 ohm, ±20%, balanced; also 50 ohm, 50 ohm setting; also 200 ohm, later spec sheet "200 or 50 Ohms"; earlier leaflet 200 ohms. "50/250 ohms, balanced, deviation ±20%, (switchable)"; set with a screw on the bottom of the CP-3B (p. 5). | p. 3 |
| Rated frequency range | 30 Hz to 16 kHzwithin 5 dB. "Frequency range; 30 - 16,000 cps within 5 db." | |
| Powering | CP-3B power supply, AC 100, 117 or 220 V, 50/60 cps, 10 VA"AC 100, 117 or 220 volts 50/60 cps, 10 VA"; the CP-3B replaced the earlier CP-3 (p. 2). | |
| Low cut | M, M1, V1, V2; four-position switch on the CP-3B power supply"By turning the 4-position switch located on the front panel, low frequency response is varied. The switch position M corresponds to the flat response, and when the switch turned to M1, V1 and V2, the degree of low frequency attenuation is increased respectively." The later sheet lists "Low-cut: M2, M1, V"; the earlier leaflet V, M1 and M2. | p. 5 |
| Pad | −6 dB"ATT" positions of the impedance/level selector: "the output level is 6 db below the normal value" (p. 5); "*6 db lower level signal is available for each impedance" (p. 4). | |
| Switches | high cut: off, on"By depressing the push-button on the front panel, attenuation in high frequency is achieved. The pilot lamp just above the push-button is illuminated when the button is depressed." | |
| Connector | mic cable with type 21-5P connectors to the CP-3B; type 21-3P output receptacle on the supply3.3 and 3.4; the output is on the front panel of the CP-3B (p. 5). | p. 3 |
| Weight | 560 galso 680, with cable, later spec sheet. "Microphone - 560 g, Power supply - 2700 g." The later sheet (p. 15): "680 g (with cable)"; the earlier leaflet 1.1 lbs. | |
| Dimensions | 192 × 44 mmFig. 1 "Dimension of Model C-37A Microphone": 192 mm overall length, body 44 mm diameter (47 mm over the pattern switch, 67 mm across the yoke). | p. 7 |
| Finish | grey baked enamel and white bronze pear-grained"Gray baked enamel and white bronze pear grained". | p. 3 |
| Supplied accessories | CP-3B power supply; EC-10B mic cable (10 m); carrying case; fuse 0.5 A; two 8 V pilot lamps; 21-3P output connector; mains voltage name plates (100, 117, 220 V)"5. Construction". | p. 4 |
| Tube | 6AU6 pentode, as a cathode follower | p. 3 |
| Power supply rectifiers | Diodes 1S-125 (2) and 1S-121 (2) in the CP-3B; the earlier CP-2 used a 6X4 rectifier tube | |
| Effective output level | -52.8 dBm at 250 ohm, -53.0 dBm at 50 ohm (re 1 mW at 10 µbar); EIA rating -144.8 and -145.8 dB | p. 4 |
| Cable length | EC-10B 10 m supplied; EC-20B 20 m and EC-30B 30 m available; up to 60 m between mic and supply without effect on performance | p. 5 |
| Stand thread | 1/2" pipe thread, adaptor for 5/8"-27 supplied | p. 3 |
| From the manual early rh | ||
| Front-to-back ratioearlier leaflet | More than 15 dB from 20 to 15,000 c/s (cardioid); the omni setting "becomes directional at 3,000 c/s" | p. 3 |
| Diaphragmearlier leaflet | Plastic, 6 µm thick, gold-sputtered on one side (0.3 µm) | p. 2 |
| From the Recording Hacks page | ||
| Released | 1955 | |
Documents
- Instruction manual, Sony condenser microphone model C-37A3rd edition, February 1964
- Sony C-37A microphone brochuresEnglish advertisement and two Japanese pages
- Condenser microphone C-37Aretyped description and data, with scanned figures
- Sony C-37A | RecordingHacks.com
Each document is © Sony.
Recommended for
By recording guides, engineers and mic makers, for this mic or an earlier version of it.