Filter
Top Products
Programming Aux Channels 9 and 10
Each of these two channels has independently adjustable high-pass and low-pass filters and
provision for deriving content from any or all of the other eight channels, mixed in any proportion
you like. They are programmed from this menu:
Level adjusts the channel’s level relative to other channels,
for proper sonic balance. It is adjustable from –15 to +15 dB,
in 0.5-dB increments. When these channels are used for
special effects, it’s usually a good idea to keep their levels
low. Because these extra channels can be used in so many
ways, it is impossible to prescribe specific level settings; we
suggest starting at the lowest possible level, gradually rais-
ing it until the extra channel becomes barely audible, then
cutting the level back by a fraction of a decibel.
Delay can be used simply to synchronize the arrival time
of the programmed channel’s sound with that of the other channels. But it can also be used for
special effects, such as adding ambience. It is adjustable from 0.0 to 80.0 milliseconds, in incre-
ments of 0.5 ms. We suggest you first try increasing the delay by 0.1 ms for each foot (or per
0.3 meter) of distance from the speaker to your listening position, then try slight variations.
Setting the delay a bit shorter than the measured distance calls for may make the sound of this
channel more dominant; lengthening the delay may make it less so. If the delay varies by more
than 30 ms from the delay settings based on distance, the channel’s sound will not blend seam-
lessly with the other channels. Aux channel setup
Ch 9 (or 10) Config Setup brings up this submenu:
Filter type can be “None,” “Lowpass,” or “Highpass.”
Filter freq can be set in 5-Hz increments. The high-pass
filter, commonly used to keep bass out of small speakers,
can be set from 20 Hz to 1 kHz. The low-pass can be set
from 20 Hz to 18 kHz. The factory default setting for both
filters is 80 Hz, recommended (but not mandatory) for use
with THX, THX Ultra, and THX Ultra2 speakers and sub-
woofers. If you want bandpass filtering for special effects,
select both high- and low-pass filters.
Mix Levels
Mix Level sets the percentage and polarity (“phase”) of
the new channel’s content that comes from each of the
other 7.1 channels, in 1% increments. The settings shown
here indicate that channel 9 is set to include 10% of each
main channel’s signal, 50% of the center-channel signal,
and 5% of each surround-channel signal. The minus signs
on the surround-channel mix listings indicate that these
signals are mixed in with their polarity reversed. Reversing
the polarity of some of the “donor” channels can give you
interesting spatial effects, especially when combined with
a bit more delay than called for by the distance from you
to the Channel 9 and Channel 10 speakers.
The mix percentages need not add up to 100%. If the mix for an Aux channel was Left 25%,
Center 100%, and Right 25%, that channel would be receiving as high a center-channel signal
level as the center channel itself does, plus a bit of the left and right channels, and the center
would be 2/3 of the total signal.
Suggested mix levels for these applications can be found in “Technically Speaking,” on page 61.
Ch 9 mix levels
᭤ Left 10
Center 50
Right 10
Right surround —5
Back 0
Left surround —5
LFE 0
Exit
Ch 9 configuration
᭤ Filter 1 type Lowpass
Filter 1 freq 80 Hz
Filter 2 type None
Filter 2 freq —
Mix levels
Exit
Aux channel setup
᭤ Ch 9 config setup
—level 0.0dB
—delay 0.0ms
᭤ Ch 10 config setup
—level 0.0dB
—delay 0.0ms
Exit
ADJUSTMENTS, MENUS, AND SETUP continued
30