A DAC, or digital-to-analogue converter, is a component that converts digital audio data into an analogue electrical signal that an amplifier, headphone amplifier or active loudspeaker can use to produce sound.

Digital music is stored and transmitted as numerical data. Sources such as CD players, computers, smartphones, music streamers and televisions all use digital audio. Because loudspeakers and headphones ultimately require an analogue electrical signal, the digital information must be converted before it can be played.

A DAC receives the digital signal and uses a conversion circuit to create an analogue waveform that corresponds to the original recording. The analogue signal is then passed through an output stage before being sent to an amplifier or directly to active speakers.

Many modern hi-fi components already contain a built-in DAC. CD players, integrated amplifiers, music streamers and AV receivers commonly include digital-to-analogue conversion. A standalone DAC can also be used when you want to connect several digital sources or use a dedicated conversion and analogue output stage.

When choosing a DAC, consider the digital inputs you need, supported sample rates and bit depths, DSD support if relevant, analogue outputs and compatibility with the rest of your system.

In simple terms, a DAC acts as the bridge between digital music and analogue audio, allowing the digital information stored in your source device to become a signal that can ultimately be turned into sound.