Installation guide

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and mid-range drivers and mid-range drivers and tweeters in a tri-amp configuration,
without using a correction filter. Limit filters can also be used with this option.
3. Bypass correction or crossover for this loudspeaker, but still use limit filters - this is for
using external limit filters or crossovers (see Limit Filters below) without speaker
correction or internal crossovers (say between woofers and tweeters).
4. Disable the processor outputs for this loudspeaker - this option disables the output of the
speaker.
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Each filter can be adjusted by using low pass and / or high pass filters. This can be useful when
using a full range speaker in conjunction with a subwoofer. With Butterworth filters, the width (Q)
as well as the slope and frequency can be specified.
The optimum slope of the sub-woofer's low pass filter and the speaker's high pass filter will
depend on the fall off of the sub-woofer as frequency increases and the fall off of the speaker as
frequency decreases. Say, for example, that they naturally cross over at about 100 Hz and the
speaker's magnitude response drops off rapidly below 100 Hz but the sub-woofer only drops off
slowly above 100 Hz. Then in order to achieve a better transition between them, the low pass
filter for the sub-woofer should have a higher slope than the high pass filter for the speaker.
Note – linear phase high-pass and low-pass filters (and consequently linear phase crossovers)
create delays in the correction filters for the speakers. This delay is the length of time in
milliseconds from the start of the correction filter to the start of the speaker correction impulse-
response and can be up to 15 milliseconds. The length of the delay caused by a linear phase
filter is proportional to the slope of the filter and approximately inversely proportional to the
frequency of the filter. For example, a linear phase filter with a slope of 48 dB per octave and a
frequency of 200 Hz will create a delay of 8.02 milliseconds. A linear phase filter with a