Doepfer A-111-4 Quad Precision VCO

A-111-4 contains four precision VCOs and has individual controls, inputs and outputs for each VCO available as well as a common control and output unit. After all the A-111-4 is very similar to four A-111-3 without LFO mode but built in output mixers for the three waveforms, and a master unit for all four VCOs.

Features

• 1V/Octave CV input
• Octave switch (+1 / 0 / -1 octave)
• Tune control (range internally adjustable by jumpers: ~ 2 semitones / ~ 1 octave / ~ 4 octaves)  
• Modulation CV input
• Modulation destination:
  • upper position: exponential frequency modulation (XM)
  • lower position: linear  frequency modulation (LM) or pulsewidth modulation of the rectangle (PM), selectable via internal jumper
•  Frequency Modulation (FM) or Pulsewidth Modulation of the rectangle (PWM)
• Modulation intensity
• Triangle output, about 5 Vpp level (-2.5V ... +2.5V) 
• Sawtooth output, about 5 Vpp level (-2.5V ... +2.5V)
• Rectangle output (about 50% without external PWM), about 5 Vpp level (-2.5V ... +2.5V)
• Sync input (hard or soft sync internally selectable via jumper, CEM3340 hard sync type, see technical remarks below)
• min. 10 octaves range (with appropriate external CV)
• CEM3340 based VCO (triangle core)
• each VCO has it's own separate internal +/- power supply for each for best stability and the prevention of unwanted synchronisation of the VCOs
• 1V/Octave CV input
• Octave switch (+1 / 0 / -1 octave)
• Tune control (range internally adjustable by jumpers: 2 semitones / 1 octave / 4 octaves) 
• Frequency Modulation CV input (FM)
• FM intensity
• Triangle sum output, about 15 Vpp level
• Sawtooth sum output, about 15 Vpp level
• Rectangle sum output, about 15 Vpp level
• CV output (outputs the sum CV that is used to control all four VCOs)
  

Video