The Roland TR-55, also known as the Rhythm 55, is a pioneering analog drum machine released in 1972. It stands as one of the first products ever released by the Roland Corporation. Unlike later programmable models, the TR-55 is a "preset" rhythm box, meaning it features fixed patterns designed for accompaniment.
The unit generates its sounds using 100% analog transistor-based circuitry, producing a warm, characteristic 70s tone. It features 10 primary rhythms—including Rock ’n’ Roll, Waltz, and Bossa Nova—which can be modified using a variation knob offering 12 additional rhythmic shifts (split between 2-beat and 4-beat styles).
A standout physical feature is the electro-static touch-sensitive pad on the top panel used for starting and stopping the sequences. For sound sculpting, it includes a Balance knob that lets you fade between the "high" percussion (hi-hats/maracas) and "low" percussion (kick/snare), effectively acting as a simple mixer.
On the back, you’ll find high and low impedance outputs and a dedicated jack for a start/stop footswitch. Because it predates modern standards, it lacks MIDI or DIN sync, making it a sought-after piece for collectors and musicians looking for authentic, vintage textures.