Niles Audio SYMPTOM SI-2125 - Manual (Page 6)

ed
he
he
ate
hat
If
xer
ce
he
et.
mal
ful
ble
ve
Turn-On Modes
The SI-2125 draws more current than a preamplifier’s switched AC outlet can
safely supply. Also, your preamplifier may “thump” at dangerous volumes if the
amplifier is already on when the preamp turns on. It is usually best to turn the
amplifier on only when it is needed. The Turn-On Mode selector switch gives you
three options for turning the SI-2125 on and off.
Constant - The auto turn-on circuitry is off. The front panel master power switch
operates the amplifier. In is “On”, out is “Off”.
Audio Sense - The master switch on the front panel must be in the “On” position.
The amplifier is off when there is no audio signal present at either the left or the
right input, but the sensing circuitry is on. The turn-on sensing circuitry looks for
a tiny amount of audio signal present at any of the audio inputs. If it detects a
signal, the amplifier is turned on. Once the audio signal stops, the sensing circuit
waits two minutes, then turns the amplifier off.
3-30 Volt AC/DC Opto-Isolated Voltage Trigger - The master switch on the front
panel must be in the “On” position. The amplifier is off when there is no 3-30V AC
or DC voltage detected at the trigger input. Once the sensing circuitry detects a
voltage, the amplifier is turned on. Once the voltage stops, the sensing circuit
instantly turns the amplifier off. Voltage triggers can be supplied by Niles automated
switchers, some video projectors, some surround sound processors, or something
as simple as a 16 volt AC wall adapter (Niles XF00008) plugged into the switched
outlet of your stereo receiver. DO NOT USE A DC WALL ADAPTER. The long
discharge time of the DC adapter’s filter capacitor will delay the turn-off of the
amplifier.
If you are using a wall adapter or external power supply to provide the trigger, it
doesn't have to be very large (a minimum current capability of 2.5 milliamps for a 3
volt trigger increasing up to a minimum of 38 milliamps for a 30 volt trigger).
INST
ALLA
TION CONSIDERA
TIONS
6
DS00354A MY/SI-2125 10/10/03 11:12 AM Page 7