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-V70'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 20 kHz using a 14.4 volt power supply with no more than
- 4-ohms: 60 watts RMS x 4 + 250 watts RMS x 1
- 2-ohms: 90 watts RMS x 4 + 350 watts RMS x 1
- 4-ohm bridged: 180 watts RMS x 2
Signal-to-Noise: When measured under CEA-2006 conditions
(reference 1 watt into a 4-ohm load) the signal to noise ratio is 87 dBA.
Measured at the rated power output S/N is 104 dB for channels 1-4 and 110 dB for
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-V70
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-V70's gain can be independently set for the
front, rear, and sub channels. The line-level input gain setting is
continuously variable from 200 mV to 4.0V (100mV to 4.0V for the sub channel); the speaker-level input gain setting
is continuously variable from 500 mV to 10.0V (250 mV to 10.0V for the sub
Input Switches: The amp has two input channel selector
switches. One determines which set of inputs feeds the rear channels (3 and 4).
You can set the switch to "1/2" or "3/4". The other switch determines which
input channels feed the subwoofer channel. You can set the switch to "1+2+3+4"
or "Sub W."
Crossovers: The amplifier has independent built-in
crossovers for the front, rear, and subwoofer channels. The front and rear
channels have a high-pass filter that can be turned on or off via a 2-way
switch. The high-pass frequency is continuously
variable from 50 to 400 Hz and the slope is 12 dB/oct. The subwoofer channel has
an non-defeatable low-pass filter with a cutoff frequency that is continuously
variable between 50 and 400 Hz and a slope of 24 dB/oct.
Subsonic Filter: In addition to the low-pass filter, the
subwoofer channel has a non-defeatable subsonic filter, which cuts ultra low
frequencies to minimize wasted power and protect speakers not capable of
reproducing those frequencies. It has a variable cutoff frequency of 5-30 Hz and
a slope of 24 dB/oct.
Bass EQ: Bass boost for the subwoofer channel is variable from 0 to +12 dB and centered at 50 Hz.
Power/Ground/Remote: The MRX-V70 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, while the Remote
Turn-on terminal will accept up to 8 gauge wire.
Speaker Output: The speaker output terminals are screw
terminals which will accept up to 8 gauge wire.
Line Inputs: Line level RCA is the preferred input
connection. There are three pairs of RCA line-level inputs. No line output is
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.