Fostex PX-5, Руководство пользователя

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E-9
Using the unit with a subwoofer
The unit is equipped with a phase-adjustable
high-pass filter so you can use the unit with a
subwoofer in the optimum condition. The high-
pass filter cutoff frequency is fixed to 85 Hz with
a slope of 36 dB/oct. By adjusting the phase of
the unit between 0 degree and 180 degrees in 20
steps, you can match the phase between a sub-
woofer and the unit, which ensures to get natural
and smooth crossover characteristics regardless
of the subwoofer’s position.
<Note>: When the high-pass filter is enabled, the
tone control setting for BASS is disabled.
Preparing a subwoofer
Set the cutoff frequency of the subwoofer to
around 85 Hz.
For details about connection and settings of the
subwoofer, see its instruction manual.
Enabling the high-pass filter
When you use the unit with a subwoofer, enable
the high-pass filter to cut off under 85 Hz.
1) Set the mode select switch to the TONE posi-
tion.
LEVEL
The upper status indicator lights steadily.
2) Press the [CONTROL] knob.
The lower status indicator lights steadily.
3) Press the [CONTROL] knob for more than three
seconds.
The lower status indicator turns off.
In this condition, the high-pass filter is enabled.
<Note>: When both of the status indicators is unlit,
the high-pass filter is enabled. When either of the sta-
tus indicators is lit, the high-pass filter is disabled.
Adjusting the phase of the
high-pass filter
1) When the unit is in the condition after step 3)
above, rotate the [CONTROL] knob to adjust
the phase of the high-pass filter.
Ideally, a subwoofer and the PX-6 should be po-
sitioned at the same distance from the listening
point. In this case, you do not need to adjust the
phase for compensation (phase adjustment: 0
degree).
The following shows some examples. The PX-6s
are used for L and R in the 2.1-channel system,
while they are used for L, C, R, LS and RS in the
5.1-channel system.
In the Fig.1 and Fig. 2, the subwoofer and the PX-
6s are positioned at the same distance from the
listening point, so you do not need to adjust the
phase.
L
R
Sub
L
R
C
LS RS
Sub
Fig. 1
Ideal subwoofer position
(2.1-channel system)
Fig. 2
Ideal subwoofer position
(5.1-channel system)