Shure Models 55 and 55SH Series II Unidyne dynamic cardioid, including the Stromberg-Carlson MC31 and the Shure 556A and 556B supercardioid microphones
The Stromberg-Carlson MC31 version of the Shure 55 Unidyne.
Specification sheet for the older Model 55A, B, and C series.
Another more comprehensive Radio’s Master catalog ad. Microphones seen on this site are not for sale. Prices are shown for historical purposes.
The Shure Model 55SH Series II Unidyne II dynamic microphone
General The Model 55SH Series II is the Shure classic UNIDYNE II design coupled with modern acoustic components to meet today’s performance standards. This microphone is excellent for vocal pickup with its characteristic Shure presence peak.
The 55SH Series II has a cardioid (uni-directional) polar pickup pattern that minimizes sound pickup from the rear of the mic. This allows the Model 55SH Series II to be used in close proximity to loudspeakers without creating feedback problems, and it can perform under adverse acoustic conditions where omni-directional microphones cannot.
The 55SH Series II has a low-impedance balanced output designed for connection to mic inputs rated at 75 to 300 ohms. The microphone features a cartridge shock mount to reduce stand noise, an ON/OFF switch, and an attached self-tensioning ⅝"-27 thread swivel mount.
Features This mic is ideal for public address, stage-theater sound systems, broadcasting, recording, and other sound applications where a stand-mounted mic with a classic look is desirable.
Classic appearance, modern performance
Frequency response tailored for speech, vocals, and instrumental music
Cardioid directional pattern for optimum performance in adverse acoustic environments
Rugged die cast case and mechanical design for reliability under rigorous conditions
Self-tensioning swivel mount, permits tilting through 45° forward and 80° backward
Specifications
Type: Dynamic
Frequency Response: 50 to 15,000 Hz
Polar Pattern: Cardioid (uni-directional), uniform with frequency, symmetrical about axis (see Figure 2)
Impedance: Microphone rating impedance is 150 ohms (270 ohms actual) for connection to microphone inputs rated at 75 to 300 ohms
Output Level (at 1,000 Hz): Open circuit voltage is −58.0 dBV/Pa (1.3 mV) (1 Pascal = 94 dB SPL). Power level: −58.5 dB (0 dB = 1 milliwatt per 10 microbar)
Polarity: Positive pressure on the diaphragm produces a positive voltage on Pin 2 relative to Pin 3 of the output connector
Switch: Built-in ON/OFF switch, integral part of swivel mount connector. Three-pin professional type, designed to mate with Cannon XL series, Switchcraft A3 (Q.G.) series, or equivalent
Case: Chrome-plated die casting
Net Weight: 624 grams (22 ounces)
The Shure Model 556A and 556B supercardioid dynamic microphones
