What has become known amongst Muff connoisseurs as the "Violet Ram's Head" was a variant of the early 70s V2 Muff that typically had unusual violet graphics rather than the more common red, and a distinctly different set of components to those associated with the more common red Ram (to make matters especially confusing, there are a few red-graphic Rams out there that sport the same or very similar components and sonic qualities as the violet ones - esp. David Gilmour's red Ram). Apparently produced for a period during 1975, it is one of the more rare and desirable Muffs and tend to go for big money.
Produced from a tracing of an outstanding sounding original pedal of '75 vintage, the 22/7 take features a set of carefully selected NOS 2N5133 transistors and metal film coupling capacitors, just like the real thing. It also features North's usual high build quality and brand-name components (Neutrik jacks/Alpha pots and quality 3PDT footswitch), true bypass switching and a standard 2.1mm 9V DC jack (battery power is also there for the purists). Oh, and that's a superbright blue LED on there.
The fabled "violet sound" falls somewhere between the "regular" Ram's Head and the earlier Triangle, combining the high gain of the former with a touch more mid-range and finesse that's commonly associated with the latter. In short, it has a deserved reputation for being a good all-rounder. Major Muff-head and massive Pink Floyd fan, Kit Rae, reckons that the violet comes closest to David Gilmour's mid-late 70s Ram sound.