audiobriefs
8:27in productionCh. 1 · An Advanced Preset Machine/ 8:27 · ceiling 15 min
Synths & drum machines

Korg Rhythm 55 KR-55

Korg

A groove box that gives you swing and levels—but never a single new beat.

The KR-55 is a fixed-rhythm drum machine from 1979. It plays 48 preset patterns across genres including Waltz, Samba, Rhumba, Bossa Nova, Tango, Slow Rock, Swing, and Rock. It uses sample-based synthesis for 12 drum tones. It has individual level controls per drum sound per pattern. A dedicated swing knob alters groove feel. A footswitch jack enables external Start/Stop and Intro/Fill control. It has no keyboard, no pattern editing, no MIDI, no sync outputs beyond footswitch, and no individual drum outputs.

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Chapters & takeaways5
  1. 0:59
    An Advanced Preset Machine

    It was advanced for 1979—not because it was programmable, but because it packed 48 grooves into a desktop unit with hands-on controls.

  2. 2:14
    The Whole Gamut of Presets

    Its patterns cover Waltz, Samba, Rhumba, Bossa Nova, Tango, Slow Rock, Swing, and Rock—no gaps, no genre experiments.

  3. 3:20
    Swing Is a Knob, Not a Setting

    Swing isn’t an effect—it’s a dedicated knob that shifts the groove’s pulse without altering timing values.

  4. 4:25
    Levels Change With the Pattern

    Each drum sound has its own level control per pattern—so the snare can punch in Rock but recede in Waltz.

  5. 5:37
    Footswitch Control, Not Just Tap Tempo

    Start/Stop and Intro/Fill respond to an external footswitch—no hands needed once you’re playing.

Worth your time?

Yes. Use the whole thing.

3.5/ 5
What works
  • groove variation via swing knob
  • pattern-specific level balancing
  • immediate footswitch control
What does not
  • support pattern creation
  • offer tempo automation
  • provide individual drum outputs
  • include MIDI
Use it if
  • players who need fixed, tactile groove control
  • performers using footswitches live
Skip it if
  • producers building custom rhythms
  • users requiring modern sync or DAW integration
The written brief1 min read

What it is and what it was built for

A 1979 desktop preset drum machine built to provide ready-made rhythmic backing for solo performers and small bands.

How it works, in terms a player would use

It plays 48 preset rhythm patterns. Each pattern triggers 12 sample-based drum tones. A knob adjusts swing. Individual level knobs set volume per drum sound per pattern. A footswitch jack controls Start/Stop and Intro/Fill.

What it does better than anything else

It delivers immediate, hands-on control over groove feel via swing and per-instrument level—within rigid presets—more directly than any earlier Korg rhythm unit.

What it does badly

It cannot create new patterns. It cannot change timing resolution or tempo in real time. It cannot layer or mute individual voices mid-pattern. It has no output for individual drum sounds.

What people made with it

No verified claims about specific recordings or artists using it. The sources do not name any music made with the KR-55.

Who should use it, and who should not

Players who value physical immediacy over flexibility. Not for producers needing custom rhythms, quantisation, MIDI, or multi-track integration.

Is it worth your time

Yes—if you want a fixed, tactile, 1979 groove engine with no sequencing, no editing, and no sync beyond footswitch triggers.

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