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Audio Adjustment <Network>
What is the multi-amp system?
The multi-speaker system reproduces each frequency band (high, mid, low and ultrabass-
ranges) through its own exclusive speaker unit. The multi-amp system provides an
exclusive power amplifier for each speaker unit.
There is only limited space in a vehicle for installing speakers, and it is difficult to install
large-diameter speakers in a door or on the dashboard and get high sound quality. To over-
come this problem, tweeters (high-range) are sometimes installed in the dashboard in order
to move the sound image upwards, or the subwoofers are installed in the rear tray in order
to improve bass and ultrabass reproduction. Thus, using a multi-speaker system can correct
imbalances in the sound image and significantly improve the total sound quality.
The multi-amp system offers the following features, allowing direct operation of the exclu-
sive speaker unit for each frequency range by an exclusive power amplifier.
• It is possible to reduce the modulation distortion rate since high-range signals are not
effected by strong signals in the low range.
• As it is possible to select amplifiers and speakers to suit the characteristics of each fre-
quency range, the load on each unit is reduced, ensuring optimum performance.
Under the multi-amp system, it is necessary to divide the audio signals into each frequency
range (band) and strictly control the set up conditions, using the network.
Under this system, the audio unit incorporates a network. The following adjustments can
be conducted within the vehicle.
• Time alignment adjustment function : adjusts for the difference in the distance
between the listener and each speaker unit.
• Filter function : sets up a low pass filter and high pass filter to
decide the reproduced frequency band, the
level and the phase of each speaker unit.
As the audio signals are processed in the form of digital signals when the network is work-
ing, the sound characteristics that best fit the vehicle interior may be created without any
deterioration in sound quality.
