Built in April 1973, this is one of the last hand-wired amps before Marshall switched to circuit board assembly. This amp features the long-style headshell, which fits snugly into the indentations on top of 4x12 cabinets. The design isn’t far removed from the classic ‘Plexi’ formula, so the sound retains that signature characteristic crunch we know and love. Internally, a few parts have been changed, which you refer to the circuit picture for further details. Other than the phase inverter, most of the original Philips coupling caps are still intact, so the sound remains well preserved. Upgraded with Jan Phillips 12AX7s in V1 and V3 phase inverter.