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Features
Connections
Specifications
Features
Power Output: The SI-2125
delivers 125 watts per channel at 8 Ohms, 200 watts per channel at 4 Ohms, and
300 watts bridged at 8 ohms.
Audio Circuitry Construction:
The audio circuitry of the SI-2125 is constructed using 1% metal film resistors,
high quality capacitors, and oversized heat sinks, allowing the amplifier to
create sound that is clear and uncolored with great imaging.
Independent Power Supplies:
Each channel of the SI-2125 is powered by its own
independent power supply. This increases the isolation between the two channels
and eliminates cross talk.
High-current Design:
The toroidal transformer has two separate
windings for each of the power supplies, providing more than ample current to
your system.
Oversized Heat Sinks: The
oversized heat sinks inside the SI-2125 allow the amplifier to stay cool even
when operating into low impedance loads without the noise of fan-cooled
amplifiers.
Independent Level Controls:
Each channel has its own independent level control enabling you to precisely
match the SI-2125 to the rest of your system.
Turn-On Modes: 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 power switch operates the amplifier.
- Audio Sense: the power
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.
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 Voltage
Trigger: the power 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.
Automatic Protection:
The SI-2125 is equipped with sophisticated protection circuits. The red "Protect" LED indicates the amp
has shut down because there is a fault in the speaker, the wiring, or with the
SI-2125 itself. When conditions return to normal, regular operation resumes.
Connections
Trigger Input (3-30V):
minijack
12V Control Output (150A
maximum): minijack
Main Input: left and right
RCA audio jacks
Cascade Output: left and
right RCA audio jacks
Speaker Outputs: left and
right gold-plated 5-way binding posts that will accept up to 12-gauge bare
wire
Specifications
Continuous Average Power
Output:
- 125 watts per channel RMS at 8 ohms
- 200 watts per channel RMS at 4
ohms
- 300 watts bridged channel RMS
at 8 ohms
Input Impedance: 10k ohms
Input Sensitivity: 0.878V
for 8 ohm rated input
Overall Voltage Gain: 33 dB
Frequency Response: bandwidth limited from 10 Hz to 100 kHz
Total Harmonic Distortion:
- 8 Ohms: 0.05% THD from
20 Hz to 20 kHz @ full rated power
- 4 Ohms: 0.03% THD from
20 Hz to 20 kHz @ full rated power
