Overview: The Niles Audio SI (System Integration) Amplifiers are
designed to power your custom-installed Audio-Video system. They are constructed
with the finest materials available, including 1% metal film resistors, high
quality capacitors, and oversized heat sinks, that can properly cool the unit
without the need for a noisy fan. The SI-1230 Series 2 is a high-current
12-channel amplifier that can help you interface multiple sources into multiple
BusMatrix Selectors: Each of the amplifier's 12 channels are
fully configurable. The unique BusMatrix selector found on each channel on the
back panel, allows each channel to select the left bus input, right bus input, left + right bus
in summed stereo, or the channel's dedicated input via dip switches. Each
channel also has independent rotary level controls.
Power Output: The SI-1230 Series 2 12-channel power amplifier provides
30 watts RMS per
channel at 8 ohms, and 40 watts RMS per channel at 4 ohms with all channels
driven. You can bridge adjacent channels to 80 watts RMS into 8 ohms.
Line Level Inputs: The SI-1230 Series 2 amplifier has a single gold-plated RCA input jack
for each channel, plus a stereo bus input. If you are bridging any of the
adjacent channel pairs, the single input from the even-numbered channel is used.
The bus input provides an audio signal to all 12 channels.
Cascade Audio Outputs: The unit's Cascade Audio Outputs
enable you to daisy-chain another amplifier, by connecting the preamp output of
the SI-1230 Series 2 to the input of the second amplifier. The outputs are not buffered,
so if you wish to daisy-chain more than 5 Niles SI Amplifiers, you will need a
buffered distribution amplifier, such as the Niles AVDA-3.
Bridging Adjacent Channels: The amplifier's 12 channels are
configured in pairs (1&2, 3&4, etc.). Each channel can be used independently (30
watts) or bridged to provide more power (80 watts) to speakers in large rooms or
for outdoor speakers. Each pair of channels has a bridging switch, which can be
activated to provide a more powerful speaker output.
Speaker Terminals: The amplifier is equipped with binding post speaker terminals. The terminals will accept single- and
dual-banana plugs, pin connectors, and bare wire up to 12-gauge. For
most applications, 16- or 18-gauge wire is recommended. For wiring runs longer
than 80 feet, 14-gauge wire is recommended.
Note: The speaker terminals have a collar around them
that prohibits the use of spade lugs.
Speaker Loads: Each channel can drive a 4-ohm load, allowing
you to connect no more than two 8-ohm speakers, or no more than one 4-6 ohm
speaker. A channel pair that has been bridged can handle an 8-ohm load. Proper
ventilation of the amplifier is required when driving lower impedance loads or
if bridging channels.
Independent Level Controls: The SI-1230 Series 2 has independent level controls
for each channel, allowing you to set the volume in each zone, or
compensate for sonic imbalances created by room size or architecture. You can
also use the volume controls to limit the volume to certain zones to prevent
Turn-on Modes: For convenience, the SI-1230 Series 2 offers three turn-on modes.
Using the 3-way switch on the back panel, you can choose from the following
- Manual Turn-on: The amplifier is turned on and off using the
front panel Master power switch. The automatic turn-on circuitry is turned
off. (Switch position: Constant)
- Music Sense: The amplifier turns on automatically when the
presence of an audio signal is detected on any of the audio inputs.
When the audio signal is no longer detected, the amplifier turns itself off
after approximately 2 minutes. (The front panel Master switch must be in the
On position, and the Turn-on Mode switch position is set to Audio Sense.)
- External Trigger: The amplifier turns on automatically when a
signal is detected at the 3.5mm AC/DC trigger input. Once the Trigger
voltage is turned off, the amplifier automatically turns itself off. Voltage
triggers can be supplied by a variety of sources, including surround sound
processors, video projectors, and automated switchers. The trigger signal
must be 3-24 volts AC or DC, 20 mA or greater. (The front panel Master
switch must be in the On position, and the Turn-on Mode switch position is
set to 3-30V AC/DC Trigger Input.)
12-volt Control Output: In addition to the 12-volt Trigger Input, the
SI-1230 Series 2 can be used to control other devices using 12-volt triggers, such as
motorized screens and curtains. When the
amplifier is powered on, a 12-volt DC (150 mA) signal is present at the 12V
Control Out 3.5mm mini-jack. (Polarity: tip = +)
Rack-mount Ears: The SI-1230 Series 2 comes with a pair of rack-mount ears to
allow you to mount the amplifier in a standard equipment rack. The rack ears
attach to the sides of the amplifier chassis using the 4 installed screws. The
amp requires three rack spaces (3U) with the feet removed.
Note: A minimum of 7" of free air space must be provided above the
amplifier for proper ventilation.
Independent Protection Circuits: Each channel his its own
independent thermal and short circuit protection. If a problem occurs on one of
the channels, that channel will shut down, while the other channels continue to
play. Once the short has been removed or the temperature returns to normal, the
channel will resume regular operations. A bi-color LED on the front panel will
glow red if the protection circuit has been activated, or green to indicate the
amplifier is operating normally.
Removable AC Cord: The SI-1230 Series 2 comes with a 6' detachable,
heavy-duty power cord that allows you to unplug it either at the amp or at the
wall outlet. The amplifier uses an IEC 3-prong cord. The amplifier features an
auto-switching, 110V-230V power supply.