Roland JC-120 Jazz Chorus

The JC-120 is a guitar amplifier: a broad, low combo in a black cabinet edged with rows of rivets, set on castors, its two 12-inch speakers behind a silver-and-black grille. Across the top runs a single panel of knobs for two channels, one plain and one with effects, and a small plate reading Jazz Chorus-120. Inside are two separate 60-watt amplifiers, one for each speaker, and no valves at all.

Roland, three years old, introduced it in 1975, when guitarists prized the warm break-up of valve amplifiers pushed hard. The JC-120 offered the opposite: a clean, hard, wide-ranging sound that leaves the guitar, and whatever pedals stand in front of the amplifier, much as they are. Its name came from its chorus. One speaker plays the guitar as it is; the other plays a copy whose pitch wavers very slightly, and the two mingle in the air of the room, so that one instrument sounds like several. Roland sold the circuit alone the next year as the BOSS CE-1, the first chorus pedal.

In Roland's catalogue of 1977 it cost ¥139,000. It found its players in new wave and post-punk, where a clean ringing guitar was the point: Andy Summers of the Police, Johnny Marr of the Smiths, Billy Duffy of the Cult. Metallica used it for their quiet passages. In Japan it became the amplifier found in nearly every rehearsal studio and live house, valued as much for being almost impossible to wear out as for its sound.

Around 1993 it gained push-button switches and an effects loop, and for about a decade from 1994 it was assembled in the United States before returning to Japan. Roland has added smaller and digital models beside it, but the 120 itself has been kept as it was: two amplifiers, two speakers, the same panel and the same riveted box.