The first thing that strikes you about the YJM100 is its size. Although it’s based on the Super Lead heads Yngwie has always used, the amp is cased up in a Marshall Major-sized box, which may be a sideways tip of the hat to Ritchie Blackmore, one of Yngwie’s biggest influences and a long- time user of the Major during his Deep Purple days. It’s deeper by about two inches compared with a standard 1959 head.
The black Levant pattern vinyl covering, gold stringing, lack of corners and small script logo all add to the YJM100’s vintage appeal, as does the gold anodised control panel with period-correct toggle switches and adjacent small ‘YJM’ logo in place of the original JMP or JTM letters.
Behind the old-school styling, the electronics are far from vintage, with one large circuit board holding all the major components and smaller boards for the front and rear panel controls. Everything is neatly assembled and tied together, giving the overall impression that the YJM100 is as robust as any modern Marshall.
From the front, Yngwie’s signature amp appears to be a completely stock classic Marshall head, with two pairs of high and low sensitivity input jacks feeding separate bright and normal channels.
Both channels have separate volume controls, but share a traditional Marshall EQ consisting of bass, mid, treble and presence. Move round to the rear and you’ll find the YJM100’s modern side, with gain and level controls for a built-in boost stage, a noise gate, digital reverb and a series effects loop.
The YJM100 also features a half-power switch and the same electronic power attenuation circuit seen on the Slash Signature head, allowing the amp’s output to be reduced down to as little as 0.05 watts in half-power mode.
The quartet of EL34 power valves is managed by a digital control system that automatically sets the bias current within a user-adjustable range; all you have to do is hold down a couple of buttons at power on. If a valve should fail, the same controller shuts down the affected pair and displays a warning LED on the rear panel.
The boost, noise gate, reverb and effects loop are all managed from a four-button foot controller that plugs in using a standard guitar lead – clever stuff.