Sound Outputs

The sound system sends computer-generated sounds to three destinations:

• built-in stereo speakers
• sound output jack
• two stereo headphone jacks.

Internal Speakers

The computer has two internal speakers. The computer turns off the sound signals to the internal speakers under the following conditions:

• when headphones are plugged into either headphone jack
• when a plug is inserted into the sound output jack
• when external USB speakers are connected
• during Sleep mode

External Sound Output

The external sound output jack is a 3.5-mm mini phone jack located on the I/O panel on the right side of the computer. It accepts a stereo miniplug-to-RCA cable adapter for connecting stereo equipment to the computer.

The sound output jack has the following electrical characteristics:

• output impedance: 65 ohms
• maximum level: nominal 1.4 V rms (4.0 V peak-to-peak)

Headphone Jacks

Two headphone jacks are located on the front of the computer next to the left speaker. Each sound output jack provides enough current to drive a pair of low-impedance headphones.

The headphone jacks have the following electrical characteristics:

• output impedance: 65 ohms
• maximum level: 1.0 V rms (2.8 V peak-to-peak)

Headphones should have an impedance not lower than the recommended minimum impedance of 32 ohms. Headphones with lower impedance can be used, but with some degradation in performance.