The release of DR-55 by Boss took place in 1980, and it became the first rhythm machine from the popular DR. Rhythm series. It was small, inexpensive, easy to use, and it is suitable for musicians of any level. Basic controls and drum timbres made this drum machine a hit among guitarists and other musicians who are looking for drum accompaniment for practicing together and even for home recording.

DR-55 can store up to six 16-step drum patterns and 2 additional 12-step patterns. The latter fits into 3/4 and 6/8 rhythms. The "Variation" switch changes patterns on the fly. The drum library consists of only 4 timbres: a bass drum, a working drum, a rimshot and a hi-hat. Sounds are comparable to the "CR" series, as well as some of the cheaper drum machines "TR" (TR-505/TR-606). You can globally adjust the volume, tempo, tone and accent of the drums.

Programming in the step mode is performed as usual: start DR-55 in the "Write" mode and select the sound from the "Sound Switch".

Next, use the "Start" button to select a sound and use the "Stop" to register a pattern. Only kick, snare, rimshot can be used for patterns in step mode, and the hi-hat can be programmed in 1/8, 1/12, and 1/16 by the appropriate switch. The drum machine was used by such artists as New Order, The Cure, Chris&Cosey and Xeno&Oaklander.