Marshall "Small Box" 50W Head from 1970 (Model 1986)
 
This amplifier is a 1970 Marshall 50-watt “Small Box” head, model 1986 — the very same type famously used by legends like Jimmy Page, Jimi Hendrix, Duane Allman, and Paul Kossoff.

Bearing serial number 9148A, this unit dates from 1970, a period widely regarded by collectors and musicians as the golden era of Marshall amplification.
 
The amp is the sought-after “small box” version, measuring 66 cm, and remains in very good condition. It features Drake transformers (with the power transformer, a 1202-324, being an 80s replacment) and retains its original Bulgin three-pin plug.
 
What makes this particular unit especially unique is its inspection label, stamped by Claude VENET, an engineer rather than a typical Marshall inspector. While most inspection labels were hand-signed and dated, VENET’s label bears only a stamp reading:
 
“Claude VENET ingénieur E.S.T.A. M.Sc, B.M.T., B.T.S., C.P.A. Toulouse”
— a list of his academic qualifications.
 
Born in Lyon, France, Claude VENET moved to the UK in 1969, where he worked as an acoustic engineer for several companies before emigrating to the United States in 1986, where he still resides today.

Although rare, Marshall inspection labels bearing VENET’s name are known to exist and are of particular interest to collectors.
 
A Brief History of the Marshall 1986
 
Originally designed as a bass amplifier, the Model 1986 quickly gained popularity among guitarists who fell in love with its distinctive tonal character. Compared to its sibling, the Model 1987 “Lead”, the 1986 featured slightly different component values, producing a rounder, thicker tone—especially well-suited to humbucking pickups and vintage-style cabinets.
Legendary Players
 
This model is associated with some of the most iconic figures in rock history:
Jimmy Page (Led Zeppelin) – Relied on Marshall during early Zeppelin tours, helping define the thunderous tones of Whole Lotta Love and beyond.
Jimi Hendrix – Famously pushed his 50W and 100W to their limits, crafting groundbreaking live tones, including his unforgettable performance at Woodstock (1969).
Duane Allman (The Allman Brothers Band) – Used Marshalls to blend warm, singing overdrive with his expressive slide guitar and signature Gibson Les Paul tone.
Paul Kossoff (Free) – Known for his thick, sustaining sound, Kossoff’s cranked Marshall remains one of the most recognizable tones in classic rock.
 
Specifications
 
Model : 1986
Serial Number : S/A 9148A
Production Year : 1970
Output : 50W
Transformers  : Original Drake (power transformer replaced with a 1980s 1202-324 Drake unit)
Chassis Type  : Small Box (66 cm)
Plug : Original Bulgin 3-pin