Bose 402 C Owner's Manual page 15

low frequency ouTPuT Mode
(bass sum)
This switch (Figure ) is very useful in systems
with only one bass loudspeaker or single-channel
bass. You can use it to combine the Channel  and
Channel  (or left and right) bass signals.
Figure 21
Even from 5 Hz to 40 Hz, some musical program
Low frequency OUTPUT MODE switch (for bass
material contains differences between the channels.
sum).
With the OUTPUT MODE set on SUM, the signal
sent to the bass amplifier is the "sum" of the signals
received by the controller.
Simply set the OUTPUT MODE switch to SUM.
Connect the left-hand LOW FREQ OUTPUT jack
(CH /SUM) to the bass amplifier.
low FreQ leVel output
Set this control between  and  o'clock (marked "0"
dB), to nominally balance a two-loudspeaker, one-
bass system with amplifiers of identical gain on the
speakers and bass. (See Figure .)
Figure 22
Since some amplifiers do not have input attenuator
LOW FREQ LEVEL output control.
controls, the LOW FREQ LEVEL control adjusts the
relative level between the bass and mid-high bands.
Rotate the control counterclockwise to 8 o'clock
to decrease the level of the signal at the LOW
FREQ OUTPUT jacks by -8 dB. Rotate the control
clockwise from 0 dB to 4 o'clock to increase the
signal at the LOW FREQ OUTPUT jacks by +3 dB.
Set this control once for initial setup and adjustment
of the system. Do not use it as a program-material-
dependent gain control.
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