Theta Digital Casablanca III HD, Owner'S Manual

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pass signal is sent to the subwoofer to augment its low bass performance. If all speaker sets are set to " FULL
RANGE " or " PHANTOM ", the following section (Steps 5-9) on setting crossovers may be skipped.
5) Determine whether or not the subwoofer can handle frequencies as high as 500Hz. If literature included with the
subwoofer does not state this specification, call your dealer or subwoofer manufacturer. Commonly only top-of-the-
line subwoofers meet this requirement.
6) If the subwoofer does meet the above requirement, first try the " PHASE PERFECT " crossover type.
7) If the subwoofer cannot handle frequencies as high as 500Hz, first try the " LINKWITZ-RILEY " crossover type.
8) Using a 2-channel CD, do the following for each of the three speaker sets ( LT/RT , CEN , SURRND ):
a) Go to that speaker sets’ configuration menu.
b) Determine if this speaker set can handle a full range signal.
c) If the speaker sets’ specification is -3dB at higher than 50 Hz, set the CFG to XOVER .
d) If the speaker sets’ specification is -3dB at 35-50Hz, set the CFG setting to FUL/LP .
e) If the speaker sets’ specification is -3dB at 20 Hz, set the CFG setting to FULL .
f) Set the crossover frequency in the Phase Perfect submenu. If a suck-out appears (lack of bass energy),
then try increasing the setting. If the transition to the sub becomes obvious, a lower frequency is
recommended.
g) Set the crossover slope in the Phase Perfect submenu. Generally, the smaller the bass driver or the fewer
the bass drive units, the steeper the required slope. A gentler slope (6dB, 12 dB / octave) is normally less
intrusive and provides better blending of the main speakers into the sub. Some sub woofers can sound
“tubby” with too shallow of a slope. A steeper slope (18dB, 24dB / octave) can provide greater dynamic
range and clearer dialog.
h) Try both settings of low pass phase. The correct setting is the one that produces the clearest, most solid
bass.
i) Repeat steps f, g and h for the Linkwitz-Riley and Butterworth crossovers, for each speaker set. In the
Butterworth crossover submenu, it is recommended that the high crossover frequency and slope be set to
the same values as the low crossover frequency and slope.
j) Set the crossover type for each speaker set.
9) In the [Center] submenu, the center channel's low pass signal may be routed to the [front left/right] channels instead
of the usual subwoofer routing ( XOVRLR ). This is useful for center channels that have extremely limited low
frequency response, i.e –3dB cutoff point around 120 Hz. Using this crossover type is an excellent tool to increase
the intelligibility of dialog.
Speaker Levels
Setting up the speaker levels is best accomplished using the Casablanca III HD’s internal noise generator and an SPL
meter. If the meter has ‘weighting’ options, “C” is preferable.
10) With Input # 1 selected, go to the speaker levels submenu.
a) Activate the noise in the front left speaker. All speaker levels should be referenced to the front left and
right speaker levels, whose reference levels should start at 0 .
b) Holding the SPL meter close in front of the user’s face, bring up the master volume (using the LEVEL
LEFT/RIGHT buttons) until the SPL meter reads 75dB.
c) Activate the noise in the front right speaker and, holding the SPL meter in the same position, adjust the
speaker level up/down until the SPL meter reads 75dB.
d) Repeat this procedure for the center speaker.
e) Activate noise in the left surround speaker. Hold the SPL meter close to the left ear, point it towards the
left surround speaker, and adjust the level until the SPL meter reads 75dB.
f) Activate noise in the right surround speaker. Holding the SPL meter close to the right ear, adjust the level
until the SPL meter reads 75dB.
g) Activate noise in the left side speaker. Holding the SPL meter close to the left ear, adjust the level until the
SPL meter reads 75dB.
h) Activate noise in the right side speaker. Holding the SPL meter close to the right ear, adjust the level until
the SPL meter reads 75dB.
i) Activate noise in the center surround speaker. Holding the SPL meter close to the left, then right ear,
adjust surround center speaker level until the SPL meter reads 75dB.
j) Activate noise in Sub1 and point the SPL meter toward the sub woofer. Adjust the SUB level until the SPL
meter reads 75dB. Note that there is greater margin for error due to the low frequency output of the sub
woofer. Listening to a familiar passage and fine tuning the sub level(s) by ear in the final adjustments will
be required.
k) Activate noise in Sub 2, if configured into the system, and point the SPL meter toward the sub woofer.