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Sound Inputs

The sound system accepts inputs from five possible sources:

built-in microphone
external stereo sound input jack
sound from internal CD or DVD player
call progress audio from the internal modem
sound from USB audio devices

Built-in Microphone

The sound signal from the built-in microphone is sent directly to the codec circuits in the Screamer IC.

External Sound Input Jack

The external sound input jack is a 3.5-mm mini phone jack located on the I/O panel on the right side of the computer. The sound input jack accepts line-level stereo signals or an Apple PlainTalk microphone. It also accepts a stereo miniplug-to-RCA cable adapter for connecting stereo equipment to the computer.

The sound input jack has the following electrical characteristics:

input impedance: nominal 2000 ohms
maximum level: nominal 1 V rms (2.8 V peak-to-peak)