ResonantLive Sound Archive

Equipment file · Valve power amplifier

Point One amplifier

H. J. Leak · 1945

Evidence status · documented

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

In 1945 Leak released the Type 15, first of its 'Point One' amplifiers, named for 0.1% total harmonic distortion at rated output. It used push-pull KT66 valves in triode connection with about 26 dB of negative feedback to deliver 15 watts. Leak had built PA and theatre amplifiers before the war.

Introduced
1945
Category
Valve power amplifier
Intended use
High-fidelity and public-address amplification
Production
H. J. Leak & Co., London

Why it mattered

  1. 01

    Deep negative feedback pushed distortion to a fraction of a percent, a new benchmark for both hi-fi and professional amplifiers.

  2. 02

    Its topology was close to the contemporary Williamson amplifier.

    Pictured in this passage
    The original Williamson amplifier schematic (1947)D. T. N. Williamson Williamson amplifierRetired electrician · Public domain

Engineering record

Output stage
Push-pull triode-connected KT66 valves, 15 watts[1]
Distortion
0.1% THD at rated output with about 26 dB of feedback[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. 1Leak Timeline44bx.com · archive

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