Doepfer A-111-3 Micro Precision VCO

The Doepfer A-111-3 Micro Precision VCO/VCLFO is an analogue VCO/LFO, with a 4HP width, a fully analogue design, a triangle core, and Tune/XM/PW controls. The Doepfer A-111-3 Micro Precision VCO has a wide frequency range, tracking at least ten octaves, along with multiple waveforms, connectivity and oscillator synchronization. It can be easily integrated into a Eurorack Modular system. Its circuit of A-111-3 is similar to the high-end VCOs A-111-2 Doepfer, but with reduced functions and controls.

The A-111-3 has two elements for frequency adjustment - a switch between LFO and VCO mode and a tune-controller whose scope is jumper selectable. The XM-controller can be used as Finetune when nothing is plugged into the XM jack. The VCO has a triangular core, generated from the sawtooth and sine pulse. The waveforms are almost ideal, and without glitches. The pulse width can be adjusted with a knob from 0% to 100% and naturally modulated. For oscillator synchronization there is an input whose type is selected with a jumper from soft to hard sync. The two syncs differ distinguishes it as the hard sync is cutting and biting.

The main features of the Doepfer A-111-3 Micro Precision VCO/VCLFO include:

• Analogue VCO/LFO
• Triangle Core
• Min. 15 Octaves Pitch Range per Mode: VCO: typ. 0.5 Hz - 20 kHz; LFO: typ. 0.001 Hz - 40 Hz
• Range Switch
• 24~ Octaves Total in Both Modes (typ. 0.001 Hz - 20kHz)
• Perfect 1V/Octave Tracking Over Min. 10 Octaves (typ. 16Hz - 16kHz in VCO Mode)
• Exponential Frequency Modulation XM Input with Attenuator
• Linear Frequency Modulation Input LM (without Attenuator), DC Coupled
• Manual Pulsewidth Control PW, Adjusts Pulsewidth from 0% (Output = Fixed at "Low" State) up to 100% (Output Fixed at "High" State)
• Pulsewidth Modulation Input PM (without Attenuator), About 5Vpp Required for Full PW Range
• Sync Input SY (Selectable Hard or Soft Sync via Internal Jumper)
• Waveform Outputs: Sawtooth, Rectangle, Triangle
• Near "Perfect" Waveforms (no Glitches)
• LED Display in LFO Mode)
• Only 4HP Panel