Rory Gallagher’s Boss GE-6 Graphic Equalizeraccess_time First seen circa 1978
Rory used an EQ pedal to get more mid-range from his amps. As far as the exact model, on Rory’s official website there are photos of the Boss GE-6. Since this pedal was produced from around 1978, it could be that Rory used it for the majority of his career.
I’ve also got a couple of Boss effects which I think are very good, a chorus, flanger, overdrive and a graphic which beefs up the mid range on the Marshall. Boss are the best effects around I think1981 issue of Music Magazine, UK
However, in a later interview, Rory states that he uses an old green Boss EQ. He was probably referring to the Boss DB-5, which was a sort of Overdrive and EQ packed in one pedal.
So the truth is that he probably juggled between these two.
I’ve got a Boss Graphic EQ. […] Yeah, one of the real old green ones.guitar for the practicing musician, August 1991 issue