Directed Electronics HCCA-D1200 Stereo Amplifier User Manual


 
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© 2006 Directed Electronics, all rights reserved
WARNING! DO NOT set crossover frequencies lower than the speakers recommended
operating range. This can cause driver failure that is not covered by the man-
ufacturer's warranty.
Low-Pass Crossover
When the switch is to the left (OFF position), the low-pass crossover is bypassed. When the
switch is in the middle (12 position), the low-pass crossover is active with a 2nd order (12dB
per octave) slope. When the switch is to the right (24 position), the low-pass crossover is
active with a 4th order (24dB per octave) slope. The low-pass crossover is continuously vari-
able from 30Hz to 250Hz.
High-Pass Crossover
When the switch is to the left (OFF position), the high-pass crossover is bypassed. When the
switch is to the right (ON position), the high-pass crossover is active with a 2nd order (12dB
per octave) slope. The high-pass crossover is continuously variable from 20Hz to 150Hz and
is optimized for use as a subsonic filter. Additionally, boost can be added at the high-pass
crossover frequency for improved bass output while still protecting the woofer from exces-
sive excursion. The INTELLi Q adjustment allows up to 10 dB of boost at the selected
crossover frequency.
WARNING! Exercise caution when setting INTELLi Q. Maximum boost can potentially
cause woofer damage due to over-excursion.
Fine Tuning the Crossovers
The low-pass and high-pass crossover sections are each marked at four frequency points for
ease of system adjustment. The low-pass crossover section is marked at 30Hz, 50Hz, 150Hz,
and 250Hz. The high-pass crossover section is marked at 20Hz, 33Hz, 90Hz and 150Hz.
Specific crossover points can be chosen based on the recommended operational bandwidth
of your speakers.
Adjusting INTELLi Q
Incorporated in the high-pass crossover, INTELLi Q maximizes the performance of a sub-
woofer. The high-pass subsonic filter removes unwanted bass output from the woofer,
increasing the output of a subwoofer by as much as 3 dB due to the increased mechanical
power handling. Depending on the enclosure, using INTELLi Q can increase the low fre-
quency response by an additional 10dB! The type of enclosure used and the woofer's excur-
sion capability determine acceptable boost levels. Listed below are recommended boost lev-
els for different enclosure designs.