Enlightened Audio Designs TheaterMaster, Руководство пользователя

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x:____Hz on the TheaterMaster front panel display, can be raised or lowered by pressing
CH+
or
CH-
on the remote control. Exit this screen by pressing the
➞
o
button.
Generally, it is good to choose a crossover frequency that is low, but well within the frequency
range of the source speaker (the high-frequency driver). Popular choices are 50, 80, 100 and
125 Hz. The factory default setting is 80 Hz.
If the LFE subwoofer has its own internal crossover network with an adjustable crossover frequency,
it is good to set this crossover frequency as high as possible (or set to “flat”) so it does not interfere
with the TheaterMaster’s crossovers. (Since the TheaterMaster already low-pass filters the informa-
tion from the source speakers before sending it to the subwoofer, it is not necessary or desirable that the
subwoofer low-pass this information again. This could produce a “hole” in the frequency spectrum.)
Alternatively, you can pick a TheaterMaster crossover frequency that is much higher than the sub-
woofer’s internal crossover frequency, and let the subwoofer crossover network do all the work.
This
approach can only be used if the source speakers are being crossed over but not rolled off.
Otherwise a “hole” in the frequency response will result.
Technical Note:
The defacto standard for professional active crossovers is the 4
th
-order (24
dB/octave slopes) Linkwitz-Riley (LR-4) design. Consisting of cascaded 2
nd
-order Butter-
worth filters, the LR-4 represents a vast improvement over the previous 3
rd
-order (18
dB/octave) Butterworth standard. The audiophile grade digital crossover filters used in the
TheaterMaster bass management circuit implementing the LR-4 design with a degree of
accuracy and consistency unobtainable in conventional analog active filter designs. Particular
attention to numerical precision; the TheaterMaster’s low-pass filter stages, for example, use
48-bit extended double precision to ensure maximum accuracy of the output signal.
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