A DCO is a type of oscillator found in synthesizers where the frequency (the pitch) is generated or controlled by a digital chip, ensuring absolute precision.

DCO vs. VCO: The Crucial DifferenceIt's important not to confuse DCO with a purely digital oscillator. Many famous analog synthesizers (like the Roland Juno-106) use DCOs. In them, the audio path is still analog, but the "conductor" that dictates which note to play is digital.

• VCO (Voltage Controlled): The pitch is controlled by electrical voltage. It tends to oscillate and go out of tune with heat or time (analog instability).

• DCO (Digitally Controlled): The tuning is controlled by a digital clock. It is extremely stable and never goes out of tune, maintaining sound consistency.