Because the official 606 specs are written in Roland's obscure ManualLanguage
(tm), here they are in Engrish:

MEMORY:
  32 patterns
  1-16 steps/pattern
  8 tracks (7 of 64 patterns, 1 of 256 patterns)

SOUNDS:
  bassdrum, snaredrum, low tom, high tom, cymbal, open hihat, closed hihat
  accent can be applied to a whole step, but not to an individual sound

CONTROLLERS:
  tempo knob (approx 40bpm - 300bpm)
  main volume knob
  instrument mix knobs (bassdrum, snaredrum, low/high toms, cymbal,
  open/closed hihats)

CONNECTIONS:
  main mix output (mono jack)
  headphone output (stereo jack)
  low tom trigger output (minijack, +14V 20ms pulse)
  high tom trigger output (minijack, +14V 20ms pulse)
  dinsync input/output
  run/stop input (jack)

POWER:
  4x C-size batteries
  AC Adaptor: DC 9V (center negative) 150mA

DIMENSIONS:
  300(W) x 146(D) x 55(H) mm

WEIGHT:
  3.7 kg


Alex Cavaye 1997