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INTRODUCTION
The SPK-1 is a two channel, speaker level A-B switch. The SPK-1 can be used to switch amplifiers,
speakers, surround sound systems, or any application where a voltage-activated speaker-level switch
is preferred.
Applying 12 volts DC to the control input connector activates the switch. A control output connector
is also provided. The control output is internally connected in parallel with the SPK-1’s control input.
The control output can be used to control additional SPK-1’s by “daisy-chaining” the control output of
one unit to the control input of the next. Connecting two SPK-1’s together enables you to switch four
channels of speaker-level signals and connecting three units together lets you switch six channels,
and so on. A maximum of 6 SPK-1’s may be connected together in this manner.
The control output can also be used to connect other Niles switching devices such as the AC-3
Voltage Activated AC outlet and the AVS-2 Voltage Activated Line-Level Switch.
The SPK-1 is designed primarily to be used as an expansion unit for the Niles SAS-1 Signal Activated
A-B Switch. The SAS-1 is an automatic A-B switch designed to replace manually operated A-B
switches. It automatically switches from A to B when a signal is present at input B. The SAS-1 can
switch any combination of line-level audio, speaker-level audio and composite video signals. Using its
control out connector, the SAS-1 can be used as the “master” unit which activates other “slave” units
such as the SPK-1, AVS-2 and AC-3. Please refer to www.nilesaudio.com for more information on
these and other Niles switching systems available.