Unusual Crossover Points - For 3-Way Systems Only; Monaural Sub-Woofer Operation - For Stereo 2-Way Systems Only - BSS Audio FDS 310 User Manual

12.0 Monaural Sub-Woofer Operation -
for stereo 2-way systems only
Fig 12.1 Mono Sub-
Woofer System
13.0 Unusual Crossover Points -
for 3-way systems only
Because human hearing is insensitive to the location of low-frequency sound
sources below 100Hz, stereo operation is normally dispensed with when
driving sub-woofers. The FDS-310 contains an internal link which can be set
to sum (mix) the incoming two channel (stereo) signals, so that the two sub-
low outputs are identical. Meanwhile, full stereo operation is retained on the
'high' outputs. Refer to section 22.2 for information on activating the sub-
woofers 'MONO mode:
The CH.1 and CH.2 'LOW' outputs will now output an identical sub-woofer
signal. At the same time, the drive levels can be individually adjusted (as
before), using the CH.1 LOW and CH.2 LOW 'LEVEL' controls. This is useful
when the two outputs are used to drive different sub-woofer amplifiers at
different locations, requiring an independent sound balance.
If there is only one sub-woofer, or the sub-woofers absolutely do not require
different drive levels and can therefore be driven from just one of the two
outputs, the unused output serves as a spare.
This is for when a 3-way system requires crossover frequencies outside the
normal range. The internal switches SW2 and SW3 (described in section 11.3)
can be used to extend the range of available crossover points downwards:
• If you require a LOW-to-MID crossover frequency below 180Hz, set SW2
'FREQ' switch to 'divide by 10'. The control will now sweep from 18Hz to
200Hz.
• Setting SW3 to the 'divide by 10' position will produce a sweep from 18Hz
to 200Hz for the MID-to-HIGH crossover frequency. This will only have
limited applications for specialist systems, and care must be taken in its use.
2-Channel Sub-Woofer Operation
Setting up -
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