Shure SM-89 (c. 1990)
Little is documented about the Shure SM-89 beyond a single thorough source: an Equipment Profile in Audio (December 1990, p.128). That profile identifies it as a shotgun condenser microphone, and the designers were clearly chasing one thing - serious output.
The SM-89 uses a combination pressure-gradient and line transducer, an electret condenser. The polar pattern is hypercardioid at low frequencies and becomes lobar above roughly 1 kHz. Rated frequency response runs 60 Hz to 20 kHz. Output impedance is 150 ohms nominal (100 ohms actual), with a recommended minimum load of 800 ohms. Output noise is rated at 16 dB equivalent SPL, A-weighted. It's a long one: 20⅝ inches (52.4 cm) overall, with a 13/16-inch handle diameter.
The review kept coming back to sensitivity. The SM-89 was rated 20 dB hotter than a typical dynamic microphone. That means it delivers the same output ten feet from a source as an ordinary mic at one foot. The reviewer was plainly taken aback, needing very little mixer gain for loud speech from 25 feet away (Audio, December 1990, p.134). The profile also described the electret backplate construction. A Shure engineer (Shulman) cited a charge of 100 V per 0.001 inch of spacing as safe from electrical pop noise.
Known specs, from the Audio profile:
- Type: shotgun condenser (pressure-gradient / line combination)
- Transducer: electret condenser
- Frequency range: 60 Hz – 20 kHz
- Polar pattern: hypercardioid at low frequencies; lobar above ~1 kHz
- Output impedance: 150 Ω nominal, 100 Ω actual; min. load 800 Ω
- Output noise: 16 dB equivalent SPL (A-weighted)
- Dimensions: 20⅝ in. long × 13/16 in. handle diameter (52.4 cm × 2 cm)
Beyond that December 1990 review, the record is thin. Production years and original price haven't been pinned down. The long barrel and big sensitivity suggest news-gathering or film-style pickup at a distance, but that's inference, not documentation.
Similar items on eBay
No exact Shure SM-89 listings are live right now — these searches show current Shure and similar vintage audio gear on eBay:
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.