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5-channel car amplifier 60 watts RMS x 4 at 4 ohms + 350 x 1 at 2 ohms
Our take on the Alpine MRX-V70 by Crutchfield's Buck Pomerantz
Digital technology that sounds perfect
Alpine's X-Power MRX-V70 5-channel amplifier uses the latest amp technology to play your music loud and clean without taking up much space. And this compact amp employs some of the same circuitry developed for Alpine's top-of-the-line PDX digital amps, so it'll bring exceptional sound to almost any ride.
One amp for your entire system
The MRX-V70 can take care of all four of your car's speakers and a subwoofer too. The 4-channel section puts out 60 watts RMS to each of your full-range speakers, so you'll have plenty of volume to fill your listening space with clear music. You can even use it in 2-channel mode to drive a pair of high-performance components with 180 watts each. Onboard frequency filters let you tailor the output to fit your setup.
The bass channel
The MRX-V70 also features a fifth channel that'll pump out up to 350 watts RMS to your subwoofer. You can use the low-pass and subsonic filters to adjust the character of your bass, while a bass boost helps to fatten up the sound if needed. An optional remote lets you control the bass level from the front seat.
Keep the music playing
A power management system optimizes the amp's performance and keeps the music playing, even when you're pushing it hot and hard for a long time. Speaker-level inputs with an automatic turn-on feature simplify system hook-up.
What's in the Box:
- 5-Channel amplifier with two 30A ATO fuses installed
- Left plastic terminal cover
- Right plastic terminal cover
- 4 Terminal cover screws (M3 x 10mm)
- 4 Self-tapping screws (M4 x 20mm)
- 2.5mm Allen wrench
- 7" Speaker-level input harness
- Owner's Manual (Eng/ Fren/ Span)
- Warranty sheet
- Online registration card
- Alpine Verification Certificate
- 5-channel car amplifier
- 60 watts RMS x 4 + 250 watts RMS x 1 at 4 ohms
- 90 watts RMS x 4 + 350 watts RMS x 1 at 2 ohms
- 180 watts RMS x 2 bridged at 4 ohms + 350 watts RMS x 1 at 2 ohms
- CEA-2006 compliant
- variable high-pass filter (50-400 Hz, 12 dB/octave) on 4-channel section
- variable low-pass filter (50-400 Hz, 24 dB/octave) on sub channel
- variable subsonic filter (5-30 Hz, 24 dB/oct) on sub channel
- variable bass boost (0-12 dB at 50 Hz) on sub channel
- optional remote level control for sub channel (RUX-KNOB)
- preamp and speaker-level inputs
- Class-D amplifier design
- MOSFET power and output stages
- fuse rating: 30A x 2
- 4-gauge power and ground leads recommended wiring and hardware not included with amplifier
- 10-5/8"W x 2-5/16"H x 9-1/16"D
- warranty: 1 year
- Our 60-day money-back guarantee
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Features and Specs
|RMS Power Output (Watts x Channels)||
60 x 4
250 x 1
|Peak Power Output (Watts x Channels)||N/A|
|Power at 2 Ohms (Watts x Channels)||90 x 4|
|Bridged Power (Watts x Channels)||180 x 2|
|Minimum Impedance Bridged||4|
|Minimum Impedance Unbridged||2|
|Best Frequency Response||5-45k Hz|
|THD at Rated RMS Power||1%|
|Signal to Noise Ratio||87 dB|
|Low-Pass Crossover Frequency||50-400 Hz|
|Low-Pass Slope (dB/octave)||24 dB/oct|
|High-Pass Crossover Frequency||50-400 Hz|
|High-Pass Slope (dB/octave)||12 dB/oct|
|Bass Boost||0-12 dB|
|Bass Boost Frequency||50 Hz|
|Speaker Level Inputs||Harness|
|Parts Warranty||1 Year|
|Labor Warranty||1 Year|
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 0.01% THD+N:
- 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 channel 5.
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 impedance).
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 500.
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 channel.
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 provided.
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.
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2 questions already asked
I can not give you an answer yet because the car in Car Shows.......... [ PAUL Apr 10, 2014 ]
I don't think so, mine are diferent impedance, Two JL 8 inch Subs and 4 of Infinity 6 1/2 kappa. Work fine [ PATRIC Apr 10, 2014 ]
I put only an 8" subwoofer in my 2013 Jeep Wrangler and I have all the bass I ever want or need. No issue at all with different ohmage. Hope this helps you. I have always relied on Crutchfield advisors for their input. I suggest asking them as well. [ WILLIAM Apr 10, 2014 ]
Not that I know of. I have had my amp for a year now and the speakers and sub are running at different ohms with no problems at all [ AARON Apr 10, 2014 ]
I checked with an Advisor and they stated: The L7 can take quite a bit more power than the Alpine amp is supplying. You are around 50% power and you would want at least 70% of the RMS power for the sub. The door speakers should be fine with the Alpine power. [ Krissy Feb 20, 2014 ] Staff