H.J.Leak and Co. Ltd. (original) (raw)

....the first name in High Fidelity since 1934

This is an un-official Leak Web Site, designed to help encourage
the restoration and maintenance of this wonderful audio equipment.

"firsts in High Fidelity"
Now Available: A fabulous book comprising the definitive and authentic history of H. J. Leak & Co. Ltd.
270 pages, 300 illustrations, 30 circuit diagrams, softbound. ISBN 1-882580-31-1
Available from:
-- Audio Amateur Corporation, USA -- Evatco, Australia --StoneAudio, UK

• Company History and Product Backgrounds

• LEAK TL/12 Amplifier
  50'th Anniversary

In December 1998 it was the 50'th anniversary of the Leak TL/12 audio amplifier. To commemorate this occasion, a special collection of information relating to the TL/12 was created.

Visit the TL/12 50'th anniversary web page:

• Introduction
• Background
• Features
• Circuit
• Restoring the TL/12New photos added
• "Point One" 1951 Booklet (28 pages - a "must see")
• Production Variations
• What Did a TL/12 Cost?
• Reviews

• LEAK Power Amplifiers

	TL/12 "Point One" power amplifier BBC Variations to the TL/12 TL/10 power amplifierTL/25A power Amplifier - not the better known "TL/25 Plus" TL/12 Plus power amplifierTL/25 Plus power amplifierTL/50 Plus (in gold and also grey )Stereo 20 power amplifierStereo 50 power amplifierStereo 60 power amplifier (with comparison to the "Stereo 50")

• Leak Pre-Amplifiers

	RC/PA and RC/PA/U Pre Amplifiers The Point One pre-amplifierThe "Varislope" Pre-Amplifier Series The original Vari-Slope, including 1952 sales brochure information.Varislope II Varislope Stereo- now with the rare gold pre-amp facsica.

• Leak Circuit Diagrams and Restoration

	Circuit Diagrams - original Leak circuits from service information sheets.A modified Stereo 50 with low gain (0.5V for full output)Restoring the Stereo 20 Amplifier (an external link - thanks to Colin Gray of South Africa) Restoring the TL/12 Output and Power Transformer Parameters and MeasurementsLeak Type 8615 Output Transformer winding arrangementStandees ResistorsParts Suppliers

• Leak AM and FM Tuners

The "VS-Radio-Tuner" for AM reception The original Leak "Trough Line" FM tuner - including how it was named. Leak Trough-Line II FM Tuner, A stereo decoder for the Trough-Line Tuner using the LM1800 decoder IC. A stereo decoder using the National SemiconductorLM1870 decoder IC. A note regarding correct de-emphasis time constants for the "Trough-Line Stereo" FM tuner. Leak Trough Line 3, and Trough Line Stereo Some alignment information for the Trough-Line.

• Leak Loudspeakers
  • The Leak "550" two-way moving coil loudspeaker
  • The Leak prototype Ribbon Loudspeaker
  • The Leak prototype Electrostatic Loudspeaker
  • Sandwich Loudspeaker - introduced around 1960 featuring advanced cone technology.
  • Modifications to the Sandwich MkII crossover that will dramatically update performance
    (PDF file; Reproduced by Permission from the Melbourne Audio News).
• Leak Curiosties and References

• Leak WWW Resources

  • "firsts in High Fidelity"
    Now Available: A fabulous book comprising the definitive and authentic history of H. J. Leak & Co. Ltd.
    270 pages, 300 illustrations, 30 circuit diagrams, softbound. ISBN 1-882580-31-1
    Available from:
    -- Audio Amateur Corporation, USA -- Evatco, Australia --StoneAudio, UK

  • Join the H. J. Leak email Group - share Leak with other enthusiasts:
    Or learn more about the H.J.Leak email group	.

H. J. LEAK & CO., LTD.

Designers and Manufacturers of Specialised Electronic Instruments for the Communications Industries

BRUNEL ROAD * WESTWAY FACTORY ESTATE * LONDON, W3

| Telephone:SHEpherds Bush 1173/1174. | | Telegrams:Inland: Sinusoidal, Ealux, LondonForeign: Sinusoidal, London | | ----------------------------------- | | ---------------------------------------------------------------------- |

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