Sony C-17B
A tiny fixed-cardioid tube condenser that Sony's own brochure claimed matched the C-37A — and the spec sheet doesn't quite back that up.
Overview
It's a fixed cardioid, half-inch capsule (15 mm) tube microphone, and it is startlingly small: roughly 4 inches long (100 mm) and about 18 mm in diameter, at just under 7 oz (200 g). The power supply, by contrast, is a boat anchor — the period documentation notes it weighed in at roughly fifteen times the microphone itself. That ratio tells you most of what you need to know about owning one: the mic is the easy part, the CP-3 supply is the commitment.
Sony's own brochure described the C-17B as "identical in performance" to the C-37A, and it's worth being clear that this was a marketing claim, not a measurement. The two mics are not the same animal. The C-37A is a large-diaphragm tube condenser with a switchable cardioid/omni pattern; the C-17B is a small fixed-cardioid capsule in a body a fraction of the size. What the C-17B actually delivers, per the published spec, is a frequency response of 30 Hz to 20 kHz at ±3 dB — a genuinely wide, flat-looking figure for a mic of its era and size, and the number that most justifies the C-17B's reputation. The tube is a 6DH3, and powering and pattern-shaping come from the outboard CP-3 supply, which also provides the high- and low-frequency roll-offs, level control, and impedance matching.
That outboard box is the whole architecture of the thing. The mic body holds the capsule and tube; everything that makes the mic usable in a real session — the filters, the level trim, the impedance selection — lives in the CP-3.
What it is not: a large-diaphragm mic, a multi-pattern mic, or a substitute for the C-37A in any application where the C-37A's switchable omni matters. The fixed cardioid is the fixed cardioid. But for close work on sources that reward a small, fast capsule with a wide, flat top end, the C-17B does the job, and it does it in a package you can hold between two fingers.
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