Wharfedale S-1500 Stereo Amplifier User Manual


 
MODE SWITCH OPERATION
LIMITER
A limiter is a circuit that prevents signal overload and distortion in an audio signal path. When engaged,
the internal limiter circuit will keep the audio signal from going over a preset level threshold, thereby
helping to prevent signal distortion within the amplifier and in the speaker system. The limiter also
serves to prevent speaker damage. The limiter function can be engaged by engaging MODE
SWITCHES SW2 (for INPUT A) and SW5 (for INPUT B) in the up “ON” position.
LO CUT
MODE SWITCHES SW3, SW4 (for INPUT A) and SW6, SW7 (for INPUT B) provide the options of low
frequency filtering starting at the 30Hz and 50Hz frequency ranges and frequencies below those points.
These filters “roll off” the lower bass frequency range to help eliminate unwanted “boominess” in the
sound system with a -12dB per octave slope. MODE Switch SW4 engages the “LO CUT” filter and
Switch SW3 selects between the 30Hz (in the up, “ON” position) and 50Hz (in the down “OFF” position).
INPUT MODE
The INPUT MODE switches select the operating mode of the amplifier. STEREO mode allows the unit
to function as a two channel amplifier with each input (INPUT A & INPUT B) routed to a separate
amplifier output (OUTPUT A & OUTPUT B), respectively.
PARALLEL mode sums the signals of INPUT A and INPUT B together and routes the combined signal
to both OUTPUT A and OUTPUT B.
BRIDGE MODE
This mode allows you to combine the amplifier outputs for more power. MODE SWITCHES #10, 11
and 12 control this function. BRIDGE MODE can provide nearly three times more power output than
operating the amp in STEREO mode.
When in BRIDGE MODE, only the controls on INPUT A are functional. INPUT B MODE SWITCH
settings have no affect on the operation of the amplifier when in BRIDGE MODE and the volume control
for INPUT B should be set all the way down when operating in this mode.
BRIDGE MODE provides a single 4 or 8 output for connection to an equivalent speaker impedance
load. Be aware of the increased power output that BRIDGE MODE provides and be sure that all
speakers have appropriate power handling capabilities before making connections otherwise speaker
damage may occur. Speaker wiring for BRIDGE MODE is made via the two middle output binding post
terminals. See pages 10 and 13 for BRIDGE MODE wiring details.
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S-SERIES Professional Amplifiers