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© 2005 Directed Electronics, all rights reserved
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 left 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 filter set to 30Hz, the woofer has more output
down to 25Hz and less overall excursion when compared to the non-high-pass response.
Maximum physical excursion capability of the woofer is 15mm.
NOTE:
The left graph is the response; the right graph is the driver excursion. These des-
ignations apply to the following graphs as well.
Enclosure Type
Boost Levels
0dB
+3dB
+6dB
+10dB
Infinite Baffle
Tune above
High X-Max
Not
Not
Fs of woofer
Drivers--Tune
Recommended Recommended
above Fs of
woofer
Sealed Tune above
Tune above
High X-Max
Not
Fs of woofer
Fs of woofer
Drivers--Tune
Recommended
above Fs of
woofer
Vented
Tune to port
Tune to port
Tune to port
High X-Max
frequency
frequency
frequency
Drivers--Tune to
port frequency
Sealed Band-pass
Tune above
Tune above
High X-Max
Not
Fs of woofer
Fs of woofer
Drivers--Tune
Recommended
above Fs of
woofer
Vented Band-pass
Tune to port
Tune to port
Tune to port
High X-Max
frequency
frequency
frequency
Drivers--Tune to
port frequency
Aperiodic
Set crossover
Set crossover
Set crossover
Not
to Fs of
to Fs of
to Fs of
Recommended
woofer
woofer
woofer
