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Studio Projects C4
Photo: Studio Projects, from its manual (Recording Hacks copy), p. 6.

Studio Projects

Studio Projects C4

Small-diaphragm (20 mm) condenser pencil mic with screw-on omni, cardioid and hypercardioid capsules; sold as a matched pair

Approximate Some readings for this mic are uncertain; see the graphs.

Type
Condenser
Pattern
Omni / cardioid / hypercardioid
Sensitivity
−39 dBV/Pa
Self-noise
18 dB(A)
Max SPL
158 dB SPL
Impedance
200 Ω
Rated range
20 – 20k Hz

Frequency response

Angle
Distance

Frequency response: from the graph cardioid rh, p. 1. Recording Hacks' "Studio Projects C4 Frequency Chart: Cardioid" (CC1 cardioid capsule); relative dB. Distance, room and smoothing not stated.

Dashed: outside the rated range, or simulated (other angles and distances). Hover or tap the graphs for values.

Polar pattern

Polar pattern: from the graph cardioid rh, p. 1. Polar plot on the same image: two half-discs, 250 Hz to 2 kHz on the left and 4 to 16 kHz on the right, each taken as symmetric; 5 dB per ring, the outer ring 0 dB. Measuring conditions not stated. Approximate reading error up to about 1 dB.

Compare with other mics

All specs

From the manual (Recording Hacks copy)
Capsule20 mm, screw-on heads: OC1 omni (pressure), CC1 cardioid and HC1 hypercardioid (pressure gradient). "Omni-directional pressure (OC1 head), pressure gradient cardioid (CC1 head), pressure gradient hypercardioid (optional HC1 head)"; the pair comes with two omni and two cardioid capsules (p. 3).p. 6
Sensitivity−39 dBV/Pa, OC1 omni and CC1 cardioid capsules; also −38 dBV/Pa, HC1 hypercardioid capsule. "Sensitivity: -39dB/-39dB/-38dB", in the order of the patterns (omni, cardioid, hypercardioid); reference not printed, taken as dB re 1 V/Pa (the LSD2 beside it: "12mV/Pa=-38dB(0dB=1V/Pa)"). Recording Hacks lists 11 mV/Pa (-39.2 dBV/Pa) for each capsule.
Self-noise18 dB(A), A-weighted per IEC 268-15; also 16 dB(A), Recording Hacks, for the 2006 revision. "Equivalent Noise: 18 dB SPL, (A-weighted per IEC268-15)". Recording Hacks says the 2006 revision has "2dB lower noise (from 18dBA to 16dBA)", yet this 2007 manual still gives 18.
Max SPL158 dB SPL, with the -20 dB pad. "Max SPL: 158 dB SPL with -20dB pad"; no figure without the pad.
Signal-to-noise ratio76 dB, OC1 and CC1 capsules; also 77 dB, HC1 capsule. "S/N ratio: 76/76/77dB".
Output impedance200 ohm, less than ("<200 Ohm")
Rated load impedance1200 ohm, more than (">1200 Ohm")
Rated frequency range20 Hz to 20 kHz. "20Hz – 20kHz"; the graphs are drawn from 50 Hz.
PoweringP48 ±4 V phantom. "P48 +/- 4V".
Current draw3.1 mA. "Current consumption: 3.1ma".
Low cutoff, 75 Hz, 150 Hz; 6 dB/octave. "Low cut: 6 dB/Octave at 75Hz/150Hz"; a three-way switch on the body (p. 3: "150Hz setting will attenuate low frequencies by 6dB/octave starting at 150Hz").
Pad−10 dB; also −20 dB. "Pad: -10dB/-20dB"; it "reduces the signal level between the capsule and the circuitry" (p. 3).
ConnectorXLR-3, gold-plated
Weight92 g. "3.3oz. (92g)".
Dimensions124.5 × 20 mm. Length 124.5 mm ("4.90''"), diameter 20 mm.
Supplied accessoriesmic stand clips C4SC; foam windscreens C4WS; stereo bar SPSB; hard-shell carrying case. "offered in pairs with mic stand clips (C4SC), foam windscreens (C4WS), stereo bar (SPSB) and hard shell carrying case".
CircuitJFET follower, low-distortion output buffer; transformerless
Sold asMatched pair, with two omni and two cardioid capsulesp. 3
Changing capsulesScrew off and on; best done unplugged or with the level down (it makes "a horrendous noise")
Made byBeijing 797 Audio Co. for PMI Audio Group (Gardena, California)p. 2
Uses (maker)Omni: ambience (especially in pairs), vocal, piano, orchestral; cardioid: close miking, X-Y and ORTF pairs, drum overheads, toms, snare; hypercardioid: X-Y, ORTF, speech and dialogue, overheads, spot mikingp. 6
From the rh page
RevisionRedesigned in 2006 by Brent Casey of PMI Audio: new amplifier circuit, higher sensitivity, lower noise, and a hypercardioid capsule addedp. 1

Documents

Copies kept by Mic Archive, because manufacturers move and drop their documents. Each is © Studio Projects, unchanged, with its original address.

Recording Hacks

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