ADJUSTMENTS
CROSSOVER FREQUENCY ADJUSTMENT
To avoid
•When setting the crossover frequencies, it is best to use source materials with a lot of bass.
•Center the tone, balance and fader controls of the source unit (leaving the other controls at their previous positions).
•Set the volume of the source unit to approximately 2⁄3 of its maximum output.
FRONT CHANNEL CROSSOVER FREQUENCY SETTING:
Adjust the fader of the source unit to increase the volume level of the front speakers. Starting from the preset frequency, adjust the front channel frequency downward or upward until you get your desired sound quality. Again, there is no universal optimum setting. It depends on the size and location of the front speakers.
XM4 REAR CHANNEL CROSSOVER FREQUENCY SETTING:
Adjust the fader of the source unit to increase the volume level of the rear speaker. Just like setting the front channels, starting from their respective preset frequencies, gradually adjust the rear channel frequencies downward or upward until you get your desired sound quality.
SUBWOOFER CROSSOVER FREQUENCY SETTING
Starting from the preset 200Hz, gradually adjust the subwoofer frequency downward to 120Hz. If the bass is still “boomy” or soft sounding, adjust it downward even further until the bass sounds tight and deep. The optimum setting varies from vehicle to vehicle and from individual to individual.
OUTPUT LEVEL ADJUSTMENT
As in the case of crossover frequency adjustment, when making the output level adjustment it is best to use compact discs or cassette tapes with greater dynamic range.
•Center the tone, balance and fader controls of the source unit (leaving the other controls at their previous positions).
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•Set the volume of the source unit to approximately 2⁄3 of its maximum output.
•Starting from their respective preset levels, adjust one output level at a time. With each of the level controls, turn the level up or down until distortion develops, then retrace the path until distortion disappears.
•Optimum output levels vary with the program source (radio, tape or CD). If the optimum output levels for radio differ considerable from those for tape/CD, locate the median levels that are best for both program sources. (Before making output level adjustment for radio, first locate a FM station with strong radio signals.)
•The optimum subwoofer output level changes from time to time, depending on the volume of road noise, which in turn depends on the vehicle speed, wind speed and road surface. With the XM series
XM4 SUBWOOFER PHASE ADJUSTMENT
•In a mobile audio system where the distance of the subwoofer to the listener is different from the distance of the midrange/tweeter to the listener, an acoustical time delay might exist due to the different timing these signals are received by the listener. The overall effect would be either almost no bass or the bass seems to lag behind the highs (commonly known as “out of phase”). If this is the case, experiment with the phase inverter switch for a position that gives you more bass output from the subwoofer.
NOISE CHECK
Before mounting the XM series crossovers and the other audio components permanently, please conduct the following noise check:
•Start the engine and turn on the power of the source unit.
•Rev the engine and vary the audio volume to check for radiated engine noise. If there is an alternator whining noise or
•If no unwanted noise is detected, double check all the wiring and cables for safe placement. Then securely tighten the mounting screws of all the audio components.
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