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Features
Controls
Connections
Features
CEA-2006 Compliant: CEA-2006 is a new system of testing and
measurement methods for mobile audio amplifiers. This voluntary standard advocates
a uniform method for determining an amplifier's RMS power output and signal-to-noise
ratio. The criteria for measuring power uses a DC input voltage of 14.4 volts and
the RMS power output is measured into a 4-ohm load, with 1% or less Total Harmonic
Distortion (THD) plus noise, and at a frequency range of 20 Hz to 200 Hz, when
applicable. Signal-to-Noise ratio is measured in weighted absolute decibels (dBA)
at a reference of 1 watt into 4 ohms. CEA-2006 allows consumers to compare car
amplifiers and receivers on an equal basis. The Infinity Reference 475a under
CEA-2006 regulations is rated at 74 Watts RMS x 4 channels with a 85dBA signal
to noise ratio.
Mosfet Power: The Reference 475a's high-output PWM Mosfet power
supply ensures optimum power delivery into numerous impedances with low distortion.
Bridgeable: In addition to powering 4 full-range speakers, the
Reference 4-channel amplifier can be bridged and configured in a 3-channel or 2-channel
application. The amplifier is rated at 180 Watts x 2 at 4 ohm in 2-channel mode and 75
Watts x 2, 180 Watts x 1 at 4 ohm in 3-channel mode.
Line Level Inputs: The front and rear channels of the amplifier each
have separate line-level RCA inputs with independent gain (Input Sensitivity) controls.
The Input Sensitivity controls will accept an input signal of 100mV to 6.0 Volts. If you
are using a receiver with only one pair of preamp outputs you will need to use two RCA
Y-adapters. When using a Y-adapter, fader controls will be lost.
Protection Circuitry: The amp features 4-way protection, and will
shut itself down in the following cases:
- DC Output: DC voltage is detected on
the amplifier output
- Temperature: Amplifier is overheated
- Over/Under Voltage: Voltage at the
+12V (Battery) terminal is less than 8.5V or more than
16V
- Short Circuit: Short circuit in speaker
or speaker wire
Power and Protection LEDs: The amplifier features a Power and
Protection LED on top of the unit. The Power LED illuminates Green when the amplifier
is supplied power. The Protection LED will illuminate Red when the amplifier goes
into protect-mode.
Controls
Application Selectors: There
is an application selector for the front and rear
channels that allow you to select which channels
of the amplifier drive your front or rear speakers
and what channels drive your subwoofers. There is
also a stereo and mono (left or right) switch for
each channel of the amplifier if you want a mono
signal from either the front or rear channel.
Front and Rear Input Levels:
Individual rotary controls for the front and rear
channels of the amplifier used to match the level
of the preamp input signal.
Crossovers: The 475a has built-in high pass and low pass
crossovers for the front and rear channels. The high pass and low pass crossover's
slope are 12 dB/octave and are continuously variable from 32Hz to 320Hz and can be
controlled independently for the front and rear channels. The amplifier can
also be operated at full-range simultaneously for both front and rear channels.
- Crossover Mode Switches: Individual
slide switches for the front and rear channels used to
select Low-Pass, High-Pass or Full-Range configuration.
- Crossover Frequencies: Independent
rotary controls for the front and rear channels to set
the cutoff frequency of the Low or High Pass Filter
between 32 and 320 Hz.
Bass Boost: The Bass Boost control allows you to enhance the
bass output of your system at 50Hz up to 6dB independently for the front and rear
channels.
Connections
Preamp Output: 1 pair of gold-plated
RCA jacks (amp provides a non-filtered signal for daisy-chaining
additional amplifiers).
Preamp Input: 2 pair of gold-plated
RCA jacks.
IMS Input: This port is designed for
future Infinity expansion products.
Speaker Output: 8 Set
screw terminals for connecting speaker wires;
handles up to 8 gauge (16 gauge minimum
recommended).
Power:
- +12V: Set screw
terminal for power wire from battery;
handles up to 4 gauge wire (8 gauge
minimum recommended)
- Remote: Set screw
terminal for remote turn-on lead; handles
up to 8 gauge wire (18 gauge minimum
recommended)
- Ground: Set screw
terminal for ground; handles up to 4 gauge
wire (8 gauge minimum recommended)
Fuses: 2 Slots for 35A ATO
fuses (installed)
