The Doepfer A-110-1 is a classic analog VCO designed as a foundational audio source in any Eurorack system. It features four simultaneous waveform outputs—sawtooth, pulse, triangle, and sine—and offers a stable pitch range over approximately 3.5 octaves once warmed up.

Pitch control includes a five-position octave switch and a fine-tune knob. The module accepts two CV inputs for frequency control: one with a 1V/oct standard and another with an attenuator for modulation depth. A dedicated sync input allows for hard synchronisation to another oscillator.

The pulse output features manual and CV-controllable pulse width modulation, allowing a full range from 0% to 100%. At extreme settings, this can cancel the waveform, offering creative modulation potential. The A-110-1 is a dependable workhorse oscillator, well suited to both melodic and complex modular patches.