Phase Switch - REVELL Concerta B12 Owner's Manual

Subwoofer Level (Volume)
Control
Provides basic volume adjustment for the subwoofer.
Begin with this control set to the nominal "12 o'clock"
position.
Low-Pass Frequency Control
50Hz
150 z H
Nom.
Min Max
Figure 15: Rear-panel controls and connectors
Adjusts the variable 50Hz – 150Hz low-pass crossover,
which determines the highest frequency at which the
B120 reproduces sounds. Set the crossover to a lower
frequency setting, between 50Hz and 100Hz, when using
larger main loudspeakers that can comfortably
reproduce some low-frequency sound.
With a lower frequency setting, the B120 subwoofer
concentrates on reproducing the deep bass required
by contemporary music and film soundtracks. Set the
crossover to a higher frequency, between 100Hz and
150Hz, for smaller bookshelf loudspeakers that do not
extend to the lower bass frequencies.
If the frequency control is set too high, the bass sounds
"boomy" and can overpower the overall sound of the
listening room. If the frequency control is set too low,
some low frequency sound may be difficult to hear, or
may be absent altogether.
This control has no effect when using the Sub In input
or if the Low-Pass Switch, shown in Figure 17, is set to
Off (Normal) while using the wireless input, because
in both cases the receiver/processor sets the crossover
frequency.
Revel Concerta B120
Owner's Manual
Note
This control does not limit the frequency
range of the main speakers in the system. The
objective of adjusting the Low-Pass Frequency
control is to ensure that all frequencies are
reproduced while minimizing any overlap
between the subwoofers and the main speakers.
Having both the subwoofer and main speakers
reproduce the same frequencies should be
avoided, as it results in very irregular response,
since some frequencies are reinforced when
they happen to be in phase while others are
canceled because they are out of phase.

Phase Switch

0 180
Figure 16: Phase switch
Compensates for the absolute phase of the subwoofer's
output relative to the front speakers. Some associated
electronics can invert the absolute phase. Use this switch
to correct such occurrences. Proper phase adjustment
can also depend on variables such as subwoofer
placement and listener position. Use this switch, shown
in Figure 16, to maximize bass output at the primary
listening position.
o
• Select the 0 setting to set the B120 acoustic output
in phase (0 degrees) with the input.
o
• Select the 180 setting to invert the B120 acoustic
output (180 degrees) relative to the input.
Low-Pass Filter Switch
(Wireless Operation Only)
Figure 17: Low-pass switch
Activates or deactivates the Low-Pass Frequency Control
when using an optional TX1 wireless transmitter. Refer
to the "Wireless Connection" section found later in this
manual for more details.
Phase
11