Thunder I-A


Matsumoku to Jan 1987
1981 to at least 1987

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There have been at least 5 versions of the Thunder IA. Thanks to forum members Tele, Adam and Chutzpah for help in identifying the differences.

Version 1 (1981-2)

Specs (as shown in the 1981 catalogue)

  • body: laminated Ash, Maple and Walnut
  • neck: 3-piece Maple
  • fingerboard: Rosewood
  • 24.75 inch scale
  • 22 frets
  • two Magnet-F450 pickups
  • 3-way selector switch
  • controls:
    -coil tap
    -active circuit on/off switches
    -master volume, master tone, equalizer volume (Active gain)
  • brass nut knobs and bridge
  • bridge saddles are barrel shaped, like the saddles on the Thunder basses
  • this version does not have through-body stringing
  • black script logo on the headstock

As with later models, the active tone control gives plus or minus 25db off the centre (Zero) position, unlike later models the gain is variable (Up to 13db boost).

The upper strap button is fitted to the outside of the top horn.

Pics courtesy of  Ebay member boppthebutler.
The extra strap button is not original, this guitar was played for a while by a left-handed player
v1 Thunder IAv1 Thunder IAv1 Thunder IA1981 Thunder IA headstock

Version 2 (1982-3)

Specs (as shown in the 1982/3 catalogue)

  • body/neck wood specs as for Version I above
  • Westone script logo on the headstock (edit: the example below has the “bird” logo)
  • plain brass knobs
  • different bridge with through-body stringing
  • two HF450 pickups
  • different active circuit:
    -controls are master volume, passive tone, equalizer tone
    -This circuit has the same tonal control range as the earlier one but the gain is not adjustable.
    (As with the Thunder IIA the catalogue specs may be wrong – some early 1983 models still had the original adjustable gain active circuit)
  • available in Light Oak, Ash Black and Sunset Red (Red and black finishes had a natural centre stripe)
New! July 2013: Thanks to Forum member Barry for this 1983 restored model:
(Click to enlarge)

Westone Thunder IA ('83) -front full 2 Westone Thunder IA ('83) -rear full 1 Westone Thunder IA ('83) -body front 2 Westone Thunder IA ('83) -headstock front

The knobs on this resto are period correct but are not the originals.
The original saddles were brass but it was missing one when received so they have been replaced with a set of stainless steel ones.

Westone Thunder I-A 1993- wiring
Control wiring. Active circuit board is attached to the cover.

Version 3 (1983-5)

Specs (as shown in the 1983 catalogue)

  • as for Version 2, except:
    -headstock features the W ‘bird’ logo
    -the active tone knob has B-O-T (Bass, O, Treble) etched on it the same as some PEQ knobs
  • two Hammer I pickups
  • The upper strap button is fitted to the inside of the top horn
  • available in Light Oak, Apple Red or Black.
  • models with the solid red or black finishes had solid Maple bodies

Thunder IA


Version 4 (1985?)

Tentatively dated to 1985 as it seems to fall between the versions above and below.


There are several changes from the previous model.

  • coil tap and phase switches are push/pull switches
  • bridge and string retainer are steel not brass
  • nut is graphite (Common on Westones from 1984 on)
  • knobs are the Switchmaster models
  • mounting holes on the back plate for mounting the active circuit PCB have moved, presumably because of the extra height in the control cavity that the push/pull pots needed.
This is one of the very few Westone seen with no serial number

Version 5 (1985 or 86 onwards)

Production seems to have ceased around 1987/1988
Does not feature in the 1988 UK price list, but does appear in shop price lists from magazines in late 1987.


  • 1986 Thunder I-A  has different pickups (with the Westone logo)
  • coil tap and phase switches are pull/push switches on the vol and tone pots
  • pickup selector is in a different position
  • different headstock logo
  • steel bridge and saddles
  • two humbuckers
  • 3-way switch
  • passive/active coil tap and phase switches
  • volume, active and passive tone controls
Thunder IA frontThunder IA body frontThunder iA body backThunder iA headstock
Also available in black – thanks to  Steven Heddle for this picture.
The knobs on this guitar are not original, this guitar dates from May 1986 and the original knobs were brass:



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