ResonantLive Sound Archive

Equipment file · Telephone receiver

Telephone receiver

Bell Telephone · 1876

Evidence status · documented

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

Bell's receiver placed a permanent magnet wound with a coil near an iron diaphragm; line current changed the magnetic field and vibrated the diaphragm. His cylindrical 'iron-box' receiver of spring 1876 replaced a less efficient tuned-reed design, and was shown at the 1876 Philadelphia Centennial Exhibition.

Introduced
1876
Category
Telephone receiver
Intended use
Turning telephone signals back into sound at the ear
Production
Hand-built by Bell in 1876, then commercialised by the Bell organisation

Equipment photographs · 1

US patent 186,787 (1877): magnetic telephone receiver

1 / 1 · US patent 186,787 (1877): magnetic telephone receiver

US patent 186,787 (1877): magnetic telephone receiver·Alexander Graham Bell·Public domain (US patent)

Why it mattered

  1. 01

    It completed the telephone as a usable two-way system.

  2. 02

    Its magnet, coil and diaphragm motor is the ancestor of every moving-iron and moving-coil loudspeaker.

Engineering record

Operating principle
A permanent magnet with a coil near an iron diaphragm; current fluctuations moved the diaphragm to reproduce sound[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

Used in Bell's first one-way long-distance call, Brantford to Paris, Ontario, about 13 km[1]

Demonstrated at the Centennial Exhibition, Philadelphia, 1876[2]

Manuals & original documents

No authoritative manual or original document has been located for this profile.

Sources

  1. 1Replica of Bell's 1876 'iron-box' receiverScience Museum Group Collection · archive
  2. 2Alexander Graham Bell Experimental TelephoneSmithsonian National Museum of American History · archive

Contribute to the record

Know more about Telephone receiver?

Corrections, firsthand information, original documents, and credited photograph sources are welcome.

Your email is private and will not appear in the archive. Contributions are not published automatically.

Back to all equipment Back to Origins of electrical sound

Help build the archive

A missing piece? A correction?

Contribute to Resonant

Support the archive

Resonant is built one verified record at a time: research hours, archival image rights, and the hosting that keeps every era, equipment file, and citation free to read. If this archive is useful to you, a donation of any size keeps the next entry moving.

How donations are used
Venmo@mercer-aplinOpen Venmo, tap the pay field, type the handle, then send any amount.Send any amount · no account needed to viewCash App$MercerAplinOpen Cash App, tap the $cashtag field, type the tag, then send any amount.Send any amount · no account needed to view

Payments go directly to the archive’s editor through Venmo and Cash App. Resonant is an independent project rather than a registered charity, so donations are not tax-deductible and nothing is sold or subscribed to in return.