In late 2005, Marshall Amplification celebrated the 40th anniversary of the world’s first amplifier stack. To honor this achievement, the company has announced a limited edition reissue of its first-ever all-valve, 100 Watt head, the JTM45/100.
This iconic head will be sold as part of a stack that includes two 4x12 cabinets, the angled 812T40 and straight 812B40. When stacked, these two cabinets emulate the immense 8x12 cabinet that accompanied the first few JTM45/100s.

The original version of this world famous amplifier was built in late 1965 at the request of the Who’s Pete Townshend. Jim Marshall was asked to provide bigger and louder amplification to accommodate the artist’s aggressive rock ‘n’ roll and blues style, so the Marshall team of engineers developed a head based on the JTM45 preamp section but with two 50 Watt power sections as the basis for the very first Marshall 100 Watt head. Due to its unique output stage, this amplifier is often referred to as the ‘dual transformer head’.
In November 1965, these formidable amps with accompanying 8x12 cabs made their stage debut. However, the original 8x12s proved too bulky for transport and were returned in favor of stacking two 4x12 cabinets one on top of the other. Thus the Marshall ‘stack’ was born.

At a time when the face and sound of popular music was rapidly changing, players were constantly pushing back and redefining musical boundaries. The JTM45/100, with its relatively simple controls, features and circuitry was there on the front line at the beginning of this important revolution in rock music.

Marshall say that the goal for the handwired re-issue was simple — to make it as identical to the late 1965 originals as possible. As a result, the circuit, cosmetics, construction, sound and all-important dynamic characteristics have all been meticulously recreated. All of the original components and materials were used or reproduced in the JTM45/100 and the methods of construction employed in the late 1960s were revisited too. In addition, the Marshall block logo, black Levant covering, original venting, beading and piping replicate the look and style of the originals.

Details:
The JTM45/100 is extremely straightforward. Its two channels — High Treble and Normal — each have two inputs (High and Low sensitivity) and separate Loudness (volume) controls. Both channels share the amplifier’s four tone controls: Treble, Middle, Bass and Presence.

The 40th Anniversary Stack’s two 4x12 speaker cabinets (812T40 and 812B40) were designed to recreate the majestic look of the original 8x12 when stacked — with the back of the angled 812T40 being semi-open, just like the top half of the original 8x12. Just like the original 8x12, both cabs are loaded with Celestion T652 Alnico Speakers.

All 40th Anniversary Stacks are individually numbered and come with a numbered certificate signed by Dr. Jim Marshall, OBE, in a leatherette folder. Also included is a full set of dust covers. Only 250 units will be available worldwide.