This article discusses the digital sound system used in the Power Mac G4 (Digital Audio) computer.

Like other Macintosh computers, the sound circuitry and system software can create and record sounds digitally and play the sounds through the speaker inside the computer, and send audio signals out through the headphone and Apple Speaker sound output ports.

All audio is handled digitally inside the computer, including audio data from the CD or DVD drive and from devices connected to the USB and FireWire ports. Sound data is converted to analog form only for output to the internal speaker and the headphone sound output port.

The sound circuitry handles audio data as 44.1 kHz 16-bit samples. If audio data sampled at a lower rate on another computer is played as output, the Sound Manager transparently upsamples the data to 44.1 kHz prior to sending the audio data to the sound circuitry.