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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 20Hz, 50Hz, 150Hz, and 300Hz. The
high-pass crossover section is marked at 20Hz, 33Hz, 90Hz and 200Hz.
Specific crossover points can be chosen based on the recommended
operational bandwidth of your speakers.
Remote Gain Operation
The remote gain port provides easy remote access to the internal
gain structure of the HCCA power amplifier. The RGC2 plugs into the
amplifier via the 1/8” mini jack plug. The RGC2 can be installed in the
front of the vehicle to control the amplifier gain level. The RGC2 can
be used as a bass level control when used on an amplifier dedicated to
subwoofers.
Adjusting Intelli-Q
Incorporated in the high-pass crossover, Intelli-Q maximizes the
performance of a subwoofer. 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 frequency response by an additional 10dB! The type of enclosure
used and the woofer’s excursion capability determine acceptable
boost levels. Listed next are recommended boost levels for different
enclosure designs.
Enclosure Type Boost Levels
0dB +3dB +6dB +10dB
Infinite Baffle Tune above Fs
of woofer
High X-Max
Drivers - Tune
above Fs of
woofer
Not
Recommended
Not
Recommended
Sealed Tune above Fs
of woofer
Tune above Fs
of woofer
High X-Max
Drivers - Tune
above Fs of
woofer
Not
Recommended
Vented Tune to port
frequency
Tune to port
frequency
Tune to port
frequency
High X-Max
Drivers -Tune
to port fre-
quency
Sealed Band-
pass
Tune above Fs
of woofer
Tune above Fs
of woofer
High X-Max
Drivers - Tune
above Fs of
woofer
Not
Recommended
Vented Band-
pass
Tune to port
frequency
Tune to port
frequency
Tune to port
frequency
High X-Max
Drivers -Tune
to port fre-
quency
Aperiodic Set crossover to
Fs of woofer
Set crossover to
Fs of woofer
Set crossover to
Fs of woofer
Not
Recommended
Infinite Baffle Example High-Pass Set at 30Hz
By removing low frequency signal that the woofer cannot produce,
the woofer can play its capable range louder. The first example is
an infinite baffle situation. The first graph displays the frequency
response of a 12-inch woofer in an infinite baffle application without
the high-pass filter, with the filter and with the filter and the Intelli-Q
set to +3dB. As you can see, with +3dB of boost and the high pass