The history of Marshall amplifiers has become a source of great fascination and interest over three decades. In 30 years of manufacturing we have made a vast number of different models using many materials and techniques. Documentation from those early years is virtually non-existent. The pressure to build amplifiers was so great that detailed record keeping was impossible. This pressure also created anomalies in the products themselves as component and minor cosmetic changes could be phased in at any time where supplies ran out but production had to continue. The following information is a rough guide to the major changes in the most popular Marshall models since 1962. 1962 - The original production of those first JTM45 models featured the following:- Serial numbers starting at 1004; Smooth black covering: White grill cloth: Silver polished aluminium panels: No rear panel: Rectangular metal logo with red block lettering: Leather handle: Single speaker output: 5881 or 6L6 valves. Cabinets - Straight fronted, using the same logo and fret cloth: Celestion G12 15 speakers. 1963 - Production essentially the same as the above but with the following changes:- Twin speaker outputs: Black knobs with serrated edges: Changed to white engraved panels late in 63: First angled cabinets, similar finish and speakers to the straights but taller than today's 4x12. 1964 - Serial numbers begin with 2: Valves now changed to KT66's: Logo changed to gold plastic with black lettering mid year: The first combos made late 64: Speakers now changed to G12 20's. 1965 - Panel changed to gold plexi glass: Serial numbers no longer reliable: Handles changed to plastic with larger end cap: The first 100 Watt amps appeared in larger cabinets with two 50 Watt transformers, JTM45 panels, KT 66 valves and without GZ34 rectifier. The first serious combo production of models 1961 4x10 and 1962 2x12 took place. The same features as the JTM45 but with the addition of tremolo. Fret cloth changed to green flecked weave late 65. The 'stack' was born from Pete Townshend's original request for an 8x12 cabinet. Late 1965 saw the change to green fret cloth.