ResonantLive Sound Archive

Equipment file · Cardioid dynamic microphone

55S Unidyne

Shure · 1951

Evidence status · documented

Identity and core specifications are documented; some historical fields remain unavailable.

The Shure 55S 'Small Unidyne' was a smaller version of the 1939 [[shure-55-unidyne|Model 55 Unidyne]], using the same Uniphase network for single-element cardioid pickup in a smaller case with a tilting head.

Introduced
1951
Category
Cardioid dynamic microphone
Intended use
Stage, broadcast and PA vocals
Production
Shure Brothers, from 1951

Equipment photographs · 1

Shure 55S Unidyne at the Vintage Radio & Communications Museum

1 / 1 · Shure 55S Unidyne at the Vintage Radio & Communications Museum

Shure 55S Unidyne at the Vintage Radio & Communications Museum·Ethan Long·CC BY-SA 2.0

Why it mattered

  1. 01

    It brought the Unidyne principle to a more compact stage and broadcast microphone.

  2. 02

    Its directional pattern improved gain before feedback in PA systems.

Engineering record

Directional principle
Single-element Uniphase acoustic phase-shift network[1]
Mechanical design
Swivel letting the head tilt through 80 degrees[1]

Original pricing

No reliable period price located

2026 equivalent

Not calculated without a reliable original price.

Public price evidence was not sufficient to publish a defensible original figure.

Use in the field

No named deployment could be tied to this exact item by a checked source yet. Know of one? Suggest it on the contribute page.

Manuals & original documents

Sources

  1. 1Model 55S 'Small Unidyne' Dynamic MicrophoneShure Brothers · manual · 1951-05
  2. 2The Unidyne Story (1939-2014)Shure · brochure · 2014

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