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Equipment file · Omnidirectional dynamic microphone

MD 21 microphone

Sennheiser · 1953

Evidence status · documented

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

The Sennheiser MD 21 was Sennheiser's first microphone with a die-cast metal housing, built to survive field reporting and broadcast remotes. It is an omnidirectional dynamic design valued for ruggedness.

Introduced
1953
Category
Omnidirectional dynamic microphone
Intended use
Reporter and broadcast remote microphone
Production
In production for decades; later MD 21-U with XLR

Why it mattered

  1. 01

    It established Sennheiser's reputation for rugged, mass-produced broadcast microphones.

  2. 02

    Its capsule work led to the cardioid MD 421.

    Pictured in this passage
    Sennheiser MD 421 ks01Sennheiser MD 421 microphone© Kreuzschnabel

Engineering record

Frequency response
40–18,000 Hz[1]
Pattern
Omnidirectional[1]
Housing
Sennheiser's first all-metal die-cast housing[2]

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. 1MD 21-U Product SpecificationSennheiser · manual
  2. 2Sennheiser - 80 years of innovation in broadcastingSennheiser Newsroom · archive · 2025

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