MRX Amplifier Design: Class-D amplifiers boast higher
efficiency, produce less heat, and draw less current than traditional
Class-AB amps. The MRX series benefits from the technology trickledown
from Alpine's more expensive PDX amps, including Direct FET final outputs,
thermal management processor, 6-Layer Glass Epoxy PC Board; combining to create
a high-end sound quality without the bulky heat sinks required by most amps in
this power class.
STAR Topology: Alpine's unique STAR (Signal Transit for
Accurate Response) Circuit PCB design provides a single common ground for all
amp sub-blocks, preventing ground interference and minimizing internal noise.
Power Management Processor: The multi-stage Power Management
Processor continuously monitors component temperatures throughout the amplifier
and decreases power output if anything gets too hot. When playing music under heavy
loads for long periods, the circuit automatically reduces power output slightly
at first, and then further in a second stage if necessary. This two stage approach
provides an interruption free listening experience.
CEA 2006 Compliant: The MRX-M55's power ratings are measured
according to the Consumer Electronics Association CEA-2006 standards. These standards
allow you to accurately compare the rated power output of all CEA 2006-compliant
amplifiers, even different brands. Manufacturers who adhere to the standards can
display the CEA 2006 logo on their products and packaging. The power output is
measured from 20 Hz to 400 Hz using a 14.4 volt power supply with no more than
- 4-ohm: 350 watts
- 2-ohm: 550 watts
- 1-ohm: 400 watts
Signal-to-Noise: When measured under CEA-2006 conditions
(reference 1 watt into a 4-ohm load) the signal to noise ratio is 90 dBA.
Measured at the rated power output S/N is 114 dB.
Verification Certificate: The amplifier comes with a certificate
that lists the RMS power output measured from that specific amplifier. It also lists
the model number, serial number, test date, and the test conditions (voltage and
Auto Turn On: When using the speaker level inputs the X-Power
amplifiers automatically turn on when voltage is detected on the signal inputs,
making them an easy factory system upgrade.
Low Output Impedance: With low output impedance, the MRX-M55
outputs tightly controlled bass, with a damping Factor rated at greater than
LED: The top panel LED power indicator glows blue when the
amplifier is turned on.
Gain: The MRX-M55's gain is set according
to the level of the incoming signal. The line-level input gain setting is
continuously variable from 100 mV to 4.0V; the speaker-level input gain setting
is continuously variable from 250 mV to 10.0V.
Crossover: The low-pass crossover point is continuously
variable from 50 to 400 Hz and the slope is 24 dB/oct; the crossover cannot be
Subsonic Filter: The amp also has a 24 dB/oct
subsonic filter, continuously variable from 5 to 30 Hz.
Bass EQ: Bass boost can be applied to the subwoofer output;
it's variable from 0 to +12 dB and centered at 50 Hz.
Power/Ground/Remote: The MRX-M55 features set-screw terminals
for the Power, Ground and Remote Turn-on inputs. The Power and Ground terminals
will accommodate up to 4 gauge wire (Alpine recommends 4 gauge for cable runs
over 3'), the Remote
Turn-on terminal will accept up to 8 gauge wire.
Speaker Output: The speaker outputs terminal is also
set-screw terminals and will accept up to 8 gauge wire.
Line Input/Output: Line level RCA is the preferred input
connection. The full range stereo line output allows easily adding another amp
without running a second set of cables.
Speaker Level Input: Use the included speaker level input
harnesses if the connected radio has no preamp outputs.
Fuses: The amp is protected by two chassis mounted 30-amp ATO fuses.
Remote Bass Control (optional): Alpine's
RUXKNOB wired remote (sold separately), connects to the amp's RJ-25 Remote
Bass Control jack, and offers control of the subwoofer output level from the
front of your vehicle. The linear attenuation can be adjusted from 0 to -20dB.