Jump to content

Hiwatt

From Wikipedia, the free encyclopedia

Hiwatt Amplification
Company typePro Audio/Amplication
IndustryAmplification
Effects pedals
FoundedSurrey, England (1966)
FounderDave Reeves
Headquarters
England
Area served
United Kingdom, United States
Websitehiwatt.co.uk

Hiwatt (stylized in all caps) is a British company that manufactures amplifiers for electric guitars and electric basses. Starting in the late 1960s, together with Marshall and Vox, Hiwatt contributed to the sonic image popularly termed "British sound".[citation needed]

History

[edit]

Technical

[edit]

Classic Hiwatt circuits

[edit]

Input stage variations:

  • The early input circuit version (Input 1) used a traditional resistive mixer to combine the two input channels. Half of V2 went unused.
  • The later input circuit (Input 2), used both halves of V2 to do the input channel mixing.
  • The OL and LEAD input circuits (Input 3) went back to the resistive mixer, and used the second half of V2 as an additional gain stage. These can be easily recognized by the "flying" components on the V2 socket.

Phase Inverter (PI) Variations:

  • The earlier circuit (PI 1) used a cathode-follower directly connected to the PI circuit to both set the DC level and buffer the signal.
  • The middle and later units (PI 2) capacitively coupled the last preamp stage to the PI. The former cathode follower section now has its input connected to a DC voltage divider, and is used strictly as a low impedance voltage reference.

Combination I: The earliest DRs with 4-inputs used Input 1 and PI 1.

Combination II: At some point, the circuit was changed to use Input 1 and PI 2 (this version is represented by the Audio Bros and Hiwatt.com schematics). Some 4-inputs may have been made this way.

Combination III: Finally, the circuit was changed to use Input 2 and PI 2. This change was definitely in all the 2-input heads, and is represented by the widely circulated freehand-drawn schematics in Pittman and elsewhere.

The OL Model (early 1980s): Biacrown's "high gain" model moved back to the Input 1 circuit (still keeping PI 2), but used the "extra" half triode as an additional gain stage.

The LEAD Model (early 1980s): This was basically the same as the OL model, but with an extra level control after the extra gain stage, which was marked "Overdrive" on the front panel.

See also

[edit]

References

[edit]
  1. ^ Pittman, Aspen (2003). The Tube Amp Book. Milwaukee, Wisconsin, US: Backbeat Books. pp. 46–47. ISBN 978-0-87930-767-7.
  2. ^ Fryette, Steven (1 June 2018). "Signal to Noise: Being Heard-The Big Amp Revolution". Premiere Guitar. Retrieved 2 February 2024.
  3. ^ "Pete's Gear: Sound City L100 amplifiers plus Sound City L100 posing as a Hiwatt". Who Tabs. Retrieved 2 February 2024.
  4. ^ "Pete's Gear: Hiwatt CP103 and DR103W". Who Tabs. Retrieved 2 February 2024.
  5. ^ a b c Fjestad, Zachary (24 August 2013). "Trash or Treasure: Hiwatt DR103". Premier Guitar. Retrieved 2 February 2024.
[edit]
  • Hiwatt.org Hiwatt history and technical information
  • TheWho.net page documenting Pete Townshend's transition from Sound City amps to Hiwatt