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Sound Adjustment Mode

About Sound Adjustment Mode

The system has several features that allow you to adjust the acoustic characteristics inside the cabin.

Sound Data (E-iSERV Audio Customize)Download sound adjustment data from E-iSERV (website) that matches the vehicle’s interior and store in the main unit.About E-iSERV Audio Customize
CSII (Circle surround II)SRS Circle Surround II delivers a unique surround sound experience equivalent to 5.1 channels over only four speaker system:Circle Surround decoder simulates 5.1 channels from any stereo format (L/R or Lt/Rt including surround sound information), SRS TruBass that makes us feel the lost fundamental bass sound through psychoacoustic response of the brain that occurs when two adjacent harmonics are carefully selected and amplified, and SRS FOCUS that elevates the sound image vertically resulting from a patented digital sound processing technology based on the HRTF (Head Related Transfer Function) theory. is a trademark of SRS Labs, Inc.Circle Surround II technology is a registered trademark of SRS Labs, Inc.Circle Surround II (CSII) setting
PEQ (Parametric EQ)When a 3-way speaker layout is selected, a 5-band parametric equalizer adjustment can be performed for each of the Hi and Mid ranges, as well as a 1-band adjustment for the low range.When a 4-way speaker layout is selected, a 7-band parametric equalizer adjustment can be performed.Parametric equalizer adjustment (PEQ)
Time Align(Time Alignment)The delay time and level for the sound from each speaker can be adjusted in order to correct any phase mismatches in the sound resulting from the listening position.Time alignment adjustment (Time Alignment)
X-Over (Cross over)Specified frequency bands are allocated to each speaker for improved sound integration. Crossover adjustment (X-Over)
Harmonizer (Multi-harmonizer)When original sounds are converted to a MP3/WMA, ATRAC3 format, frequency ranges that are not normally audible to the human ear are compressed. The harmonizer can be used to play back these compressed sounds at as close to their original from as possible so that clear and powerful sound can be enjoyed.Multi-harmonizer settings (Harmonizer)
Non-F setting (Non-fader setting)The sub-woofer settings can be performed.Non-fader settings (Non-F Setting)
SP Layout (Speaker layout)The speaker layout can be configured as a 3-way or 4-speaker system.Speaker layout settings (SP Layout)

About parametric EQ

A variety of materials are used inside a vehicle to manufacture the seats and windows, and because these materials absorb and reflect sound in different ways, the parametric equalizer lets you adjust the peaks and dips of the frequency characteristics inside the vehicle to compensate for this.

An “equalizer” is a function that corrects these peaks and dips in order to flatten the frequency characteristics. However with a normal graphic equalizer, the median frequency and the Q (sharpness and band width) are fixed, so that when neighboring bands are corrected, there is a limit to the amount by which distortion in the peak and dip characteristics can be corrected. A “parametric equalizer” lets you adjust the median frequency, Q (sharpness and band width) and gain to variable levels, so that you can make fine adjustments to spot areas of the frequency band.

[Parametric equalizer characteristics]

1.Median frequency can be varied.

2.Gain can be varied.

3.Q (sharpness/band width) can be varied.

About time alignment

With vehicle audio systems, the installation position of the speakers and the position of the listener mean that the distances from the listener to the left and right speakers are almost always different. These differences in the distance from the listener to each speaker in turn means that the time taken for the sound to reach the listener is different for each speaker. The result of this is that the phases of each speaker (biases) become mismatched and the sound becomes unnatural, as though the sound stage is not wide enough. The “time alignment” function corrects the time taken for the sound waves to reach the listener in order to set the optimum phase for the listening position so that the sound becomes more expansive as though it is being listened to on a sound stage.

The basic adjustment method involves measuring the actual distances to each speaker and calculating the differences in distance relative to the most distant speaker in order to derive the delay time for the sound from each speaker.

About crossover

The frequency band that is stored by audio media such as CDs is a fairly wide range from 20 Hz to 20 kHz, and it is difficult for a single speaker to be able to play back all frequencies in such a wide range.

Because of this, several speakers can be used, with different frequency bands (such as treble, medium and bass) allotted to each speaker so that wide frequency ranges can be played back. The “Crossover” function is used to allot the frequency ranges that are to be played back by each speaker in accordance to the installed speaker units and the layout of the speakers, in order to obtain the maximum level of performance from the speakers and to provide the most stable frequency characteristics.

The crossover function includes a high-pass filter (HPF) for playing back treble sounds, and a low-pass filter (LPF) for playing back bass sounds. In addition, the HPF and LPF are used in combination in order to play back sounds in the mid range.

For example, when adjusting the HPF, frequencies that are lower than the specified frequency are progressively dampened, rather than simply not being played back at all. The “slope” adjustment function is the function that is used to adjust these dampening characteristics.

The slope characteristics of a filter are such that with larger slope values (for example 12 dB/oct), the slope becomes steeper, and so the amount of sound mixing in with neighboring bands becomes less so that only the target band is played back. However, it also causes the merging of sound between speakers to become poorer and can result in greater distortion.

  • The crossover function is a filter that allocates the specified frequency bands.

  • A high-pass filter (HPF) is a filter that cuts out frequencies that are lower than the specified frequency (bass range) and allows higher frequencies (treble range) to pass through.

  • A low-pass filter (LPF) is a filter that cuts out frequencies that are higher than the specified frequency (treble range) and allows lower frequencies (bass range) to pass through.

  • The slope is the signal level at which frequencies that are one octave higher or one octave lower are dampened.

When the 4-speaker layout is selected, it corresponds to basic speaker systems which comprise front speakers, rear speakers and an added sub-woofer if necessary. In such cases, the crossover can be used to apply the HPF to the front and rear speakers and the LPF to the sub-woofer so that the sound from all speakers merges properly.

When the 3 way layout is selected, the adjustments can be made to suit speaker system where the front speaker, rear speaker and non-fader output can be switched between Hi, Mid or Low output and the speakers can be combined according to each range (treble range: tweeter, medium range: Mid, bass range: woofer) to provide 3-way playback. In this case, the crossover function can be used to adjust the playback ranges so that the HPF is applied to the treble-range speakers, the HPF and LPF is applied to the medium-range speakers, and the LPF is applied to the bass range speakers so that the sound from all speakers merges properly.

About E-iSERV Audio Customize

The parametric equalizer, time alignment and crossover setting can be adjusted directly using the main unit settings, or through the ECLIPSE website. The following sound quality adjustments can be performed through the ECLIPSE website (E-iSERV):

  • Automatic parametric equalizer

    This can be used to automatically correct distortion in frequency characteristics (peaks and dips) based on the results of measuring the frequency characteristics inside the vehicle.

  • Time alignment and crossover adjustment

    How to operate the sound adjustment mode or other adjustments besides adjustment of this main unit can be carried out using the ECLIPSE website.

  • Custom mode

    Using the custom mode, E-iSERV Audio Customize allows you to make adjustments even more precise than those available with the main unit alone.

    Use the following procedure to make sound quality adjustments through the ECLIPSE website (E-iSERV):

Speaker setting
Frequency characteristics measurement/Saving sound data
After measuring frequency characteristics, sound data (frequency characteristics measurement result, crossover and time alignment adjustment values) will be written on the USB memory automatically.( Measuring/displaying frequency characteristics.)
E-iSERV (website) accessing
Access the following URL:
Sound quality adjusting
Follow the instructions given on the website.
Correction data downloading
Follow the instructions given on the website.
Correction data reading
(Importing Sound Data (Sound Data).)