• Country
• Great Britain (UK)

• Manufacturer / Brand
• Lowther Manufacturing Co; Kent

• Year
• 1954

• Category
• Loudspeaker, headphone or earphone

• Radiomuseum.org ID
• 340615

Click on the schematic thumbnail to request the schematic as a free document.

• Wave bands
• - without

• Power type and voltage
• No Power needed

• Loudspeaker
• Ø 8 inch = 20.3 cm

• Material
• Various materials

• from Radiomuseum.org
• Model: Lowther Driver Unit PM3 - Lowther Manufacturing Co; Kent

• Shape
• Chassis only or for «building in»

• Notes

• Lowther PM3

  This  8-inch twin cone driver unit was of a radical new design.

  The PM3 was specially developed for use in the Lowther TP1 corner enclosure. It incorporated one of the largest magnetic structures in use on loudspeakers.

  The PM3 driver was not sold separately.

  The design incorporates a dome-shaped member rigidly mounted to the centre pole and is described in Donald Chave’s US Patent 2,808,895.

  This member acts as a non-magnetic mechanical crossover filling the space inside the tweeter cone which provides air loading to the cone. This permits the smooth transition of low and high frequencies without dips at the crossover frequency. See Patent for a more detailed explanation.

  Specifications

  • Frequency range: 20 - 22,000 Hz
  • Gap Flux: 22,000 Gauss
  • Power Rating: 25 Watts
  • Impedance: 16 Ω 

• Mentioned in
• -- Original-techn. papers. (US Patent 2,808,895)

• Author
• Model page created by Gary Cowans. See "Data change" for further contributors.

• Other Models

• Here you find 56 models, 51 with images and 2 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Lowther Manufacturing Co; Kent