kt66

Some vintage gear carries the patina of both age and history. That’s the case with this month’s featured amp: a 1964 Marshall JTM45 4x10 combo that was owned and played by Peter Green during his years with Fleetwood Mac, and potentially with John Mayall’s Bluesbreakers.

It is a beast! This amp looks beautifully stage-worn and breaks up quickly, offering a throaty growl that sounds nicked from the studio tracks for “Rattlesnake Shake.” Output is 30 to 35 watts, but trust me, I was sitting in front of it when the sound sample you can hear online was recorded, and it bellows like a bull elephant.

The JTM45 was Jim Marshall’s first amp design, inspired by Leo Fender’s Bassman, and the model was just a year old when serial number 7217 was built as a combo with four Celestion 10" alnico speakers, now aided in their gnarly tone by decades of play. Marshall used RS De Luxe transformers, and the two preamp tubes in the ’45 are 12AX7s/ECC83s, with a third as a phase splitter, verses 12AY7s in the Bassman. That combination of preamp tube and transformer give the JTM45 it’s un-Bassman-like snarl. The amp was also built around KT66 output tubes and a GZ34 rectifier tube, with yellow-brown capacitors—so-called mustard caps—in an aluminum chassis. The control array is tremolo speed and intensity, presence, bass, middle, and treble, plus loudness for each channel. There are two channels—treble and normal—with four inputs, so they can be jumped with a short cable to add hair. And number 7217’s original channel switcher box is intact.

Photo by Max Raymond

Green’s amp was recently acquired by Eliot Michael, the owner of Rumble Seat Music—one of the holy trinity of world-class guitar shops along Nashville’s 8th Avenue. It sits along one of the store’s walls, with two certificates of authenticity above its head. I asked Michael what he’d tell a potential buyer making a query about the amp. He replied, “The person I purchased it from runs Ronnie Lane’s old studio. This was used in that studio. The Who used it, the Rolling Stones used it, and it was purchased from Fleetwood Mac when Peter Green was in the band. From what I was told, Peter didn’t have the money to pay for a certain thing, so the amp was left to them as payment.”

Photo by Max Raymond

“Them,” in this case, appears to be Fleetwood Mac’s accountant, David Simmons, who provided one of the certificates. According to Simmons, he took the amp with him to work with JAD Records and Bob Marley, and it was used for several Marley sessions. Simmons gave the amp to Mark St. John, and it began service in a variety of studios St. John partnered in, including London’s Freerange, the Basement Studio, 145 Wardour Street, and the Smokehouse, as well as Ibiza’s Studio Mediterraneo. It was also used for projects done via Ronnie Lane’s Mobile Studio. St. John’s certificate adds that other artists and groups who used this amp include David Gilmour, the Police, Arthur Brown, and Eddie Grant. “The amplifier is pretty much entirely original and has not been restored or altered, with only simple maintenance being applied to keep it operating correctly,” he wrote.