Mac OS X 10.6: Identifying audio ports
Your Mac includes one or more audio ports. Depending on your computer, it might have analog in/out, optical audio in/out, optical digital audio in/out, or a combination of these ports. You can use these ports to connect your Mac to an audio system or to connect headphones and speakers.
An icon next to the port identifies the type of port. The name of the port can be useful if you need to purchase adapters and cables for the port.
In addition to the ports above, some speakers and professional audio interfaces may use USB or FireWire ports for transferring audio data.
Analog audio in: You can use a stereo miniplug-to-RCA cable adapter to connect stereo equipment to your Mac.
Audio in/optical audio in: You can use this port for both digital optical and analog audio input. For analog audio input, use a 3.5 mm mini phone jack or a stereo miniplug-to-RCA cable adapter to connect stereo equipment. For digital optical audio input, use a standard Toslink cable with a Toslink mini-plug adapter. Digital optical audio input uses the S/PDIF protocol.
Analog audio out: You can connect self-powered speakers, MP3 and CD devices, and other audio equipment to your Mac.
Headphone: You can use this port as a combination headphone and line-out port. Connect headphones or speakers using a standard audio cable with a 3.5 mm metal plug.
Headphone out/optical audio out: You can use this port for both optical digital audio output and analog audio output. Connect external speakers, headphones, or optical digital audio equipment. For analog headphone/line output, use a standard audio cable with 3.5 mm metal plug. For optical digital audio, use a Toslink cable with a Toslink mini-plug adapter or a fiberoptic cable with a 3.5 mm plastic or nylon optical plug.
Optical digital audio in and out: You can use these ports to transfer stereo or encoded 5.1 audio using the S/PDIF protocol over Toslink cables and connect to decks, receivers, digital instruments, and 5.1 surround-sound speaker systems. Use standard Toslink cables, or fiberoptic cables with a 3.5 mm plastic or nylon optical plugs.
To learn about the audio ports available on your Mac, refer to your computer’s user’s guide. User’s guides are available online at the Apple Product Manuals website. You can also open System Profiler. Choose Apple > About This Mac from the menu bar, and then click More Info. Click the Hardware disclosure triangle, and then click Audio.