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/ INSTALLATION STEP 6 k
CROSSOVER ADJUSTMENTS
The REFERENCE644s and REFERENCE414s amplifiers incorporate an on- board staggered electronic crossover. They also have RCA outputs to drive an external amplifier. No external electronic crossover is necessary. The high and low pass portions of the crossover can be set independently of one another.
In most car audio installations, there is a tendency for a “midbass boom.” Because of their interior dimensions, most cars will resonate or ring at these midbass frequencies. If we design the system so there is less musical information in this region, the final response is very smooth and natural sounding. The high pass filter is variable from 60 to 240 Hz at 12 dB/octave, while the low pass filter is variable from 30 to 120 Hz at 24 dB/octave.
For initial crossover setup, try setting the low pass filter to approximately 60 Hz, and the high pass filter(s) to approximately 100 Hz. Change the cro~swer points to accommodate a good mixture of frequency response, power handling. and personal preference.
full range is detived from ~ When the RCA sianal outout is ~
summed from Channels I, 2; j the REFERENCE644s also !
AIRBASSTM ACCESSORY OPT/ON
Soundstream’s newA/RBASSTY feature can be added to the REFERENCE6445
&REFERENCE414s amplifiers. This feature allows wireless RF remote conlrol level adjustment of the amplifier, while the low pass filter on the amplifier’s internal crossover is engaged. (AIRBASS TM does not control the level of the
RCA signal outputs.)
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NOTE: The A/RBASSTM accessory ;s intended to be used only while the REFERENCE amplifiers are diving a subwoofer( When the AIRBASSTH accessory is added to a REFERENCE414.s a n d REFERENCE644q it controls the level of any channel receiving informabon from the low pass filter in the amplifier. The Coherent StereoTM / Mixed Mono / Bridged Mono switches still function as nomlal.
Installing AiRBASS TM involves removing the bottom plate of the amplifier. adding the AIRBASSTM circuit board, and flipping a switch. The switch is labeled on the amplifier’s main circuit board. DO NOT set the AIRBASSTM switch to the “IN” position unless theAIRBASSTM module has been added. DO NOT move the A/RBASSTM switch while the amplifier is “ON”. Doing so may damage your speakers. (Please refer to the AIRBASS”* owner’s I installation manual for more details.)
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