System Description: Overview

The audio unit acts as the processor for all audio functions. You can select of the audio functions from the front panel, the audio remote (on steering wheel), or by using the navigation voice control system. The audio display provides the current front and rear audio status. For vehicles with the navigation option, additional audio information is available by touching the audio button. (See the owner's manual for more details.)

Each audio component passes its audio signal to the audio unit. In addition, it communicates with the audio unit via the GA-Net bus. Any open connection in this circuit will cause audio and navigation functions to appear inoperative.

With the premium sound system, an audio amplifier unit powers the speakers, otherwise the speakers are powered directly by the audio unit.

The system includes an active noise cancellation system to cancel some of the vehicle noise. It uses a sine-wave-shaped sound output to cancel low frequency noise. Two microphones detect the low frequency sound, and the system outputs a canceling sound through the audio speakers.

Fig 1: Sound Waveform

Courtesy of AMERICAN HONDA MOTOR CO., INC.

The 6CD changer output can be directed to the audio unit.

The XM radio plays through the audio unit.

A security signal is daisy-chained between the audio and navigation components and integrated into the vehicle's alarm system.

The optional navigation system provides voice control for the front/rear audio, the XM, and the CD player. Voice control commands are communicated through the GA-Net (audio unit). When using the TALK/BACK or route guidance (RG), only the center speaker is muted and the front speakers give the navigation instructions. When using the HFL/ AcuraLink, the center speaker, the rear speakers, and the subwoofer are muted and the front speakers give the telephone sound. When using the HFL/AcuraLink and the RG (Route Guidance) or voice response, the center speaker, the rear speakers, and the subwoofer are muted and the front speakers give the telephone sound and the navigation instructions. Muting commands are passed on the GA-Net bus. For more information, see the navigation service information. The outline of the audio interruption function is shown in the following table.