The iconic Yamaha DX7 is 16-voice 6-operator digital synthesizer that uses FM, or Frequency Modulation, to produce its sound. The DX7 sold more units than any synthesizer in history, and it's introduction in the 1980s caused an upheaval in the industry, steering many musicians away from analog synthesizers (a trend that has now been reversing). The DX7 has a 5-octave keyboard that is velocity and aftertouch sensitive.
