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250W x 1 Mono Subwoofer Amplifier
Item # 500MRDM500 | MFR # MRD-M500
This item is no longer available.
Our take on the Alpine MRD-M500 by Crutchfield's Robert Ferency-Viars
Gut-busting power and exacting control that's what you get with Alpine's V12 AccuClass-D mono bass amplifiers. The MRD-M500 amplifier has a built-in digital signal processor that lets you control the Bass Engine® features with surgical precision, giving you a level of fine-tuning capability previously found only in Alpine receivers.
Set the cut-off point for the subsonic filter from 15-50 Hz (in 5 Hz steps) and use the digital parametric EQ (which allows you to control the width of the equalization curve, as well as the center point) to improve overall sound.
The Bass Compensator uses Alpine's MediaXpander (used in their receivers to optimize playback of compressed media files) to enhance low-end definition of the amplifier's output. Monitor the temperature, voltage, and current levels using the digital readout.
Alpine's digital technology ensures extraordinary clarity. The efficient Class-D design lets your music sound like thunder without wasting a lot of energy as heat, while the lightning-fast MOSFET power supplies keep your music roaring with life.
The MRD-M500 has a set of preamp outputs for easily getting signal to another amplifier. The extra-large gold-plated wiring terminals will let your bass really hit, since larger-sized power and speaker wires let the power move more efficiently into and out of the amp.Details:
- 250 watts RMS x 1 at 4 ohms
- 500 watts RMS x 1 at 2 ohms
- MOSFET power supply and output stage
- STAR Topology for cleaner sound
- Bass Engine® features:
- low-pass digital crossover, 30-200 Hz, 24 dB/octave
- variable subsonic filter (15-50 Hz in 5 Hz steps)
- parametric EQ variable from 30-160 Hz, ±12 dB
- Bass Compensator enhances low-end definition
- top-mounted digital control center with cover
- time correction 0-10 milliseconds in 0.1ms steps
- phase adjustment 0-180°
- turn-on delay
- digital readout
- detachable front cover
- blue power LED
- preamp inputs and outputs
- requires 4-gauge power and ground leads wiring and hardware not included with amplifier
- extra-large gold-plated terminals
- 12-3/8"W x 2-11/16"H x 11-1/2"D (10"D without front cover)
- 1-year warranty
What's in the Box:
- Mono amplifier
- 1 Terminal cover
- 2 Allen head bolts to mount terminal cover
- 2 Allen wrenches
- 1 End cover
- 2 End cover mounting brackets
- 4 End cover bracket mounting bolts
- 2 Rubber terminal strip covers
- Rubber "pipe" to protect wires
- 2 Allen head bolts for speaker output terminals
- 1 Allen head bolt for remote input terminal
- 4 Sheet metal mounting screws
- 2 Strips of 2 Sided tape
- 2 Adhesive backed pads
- Customer Care Registration/Survey
- Warranty sheet
- Certificate of power output
- Note on wiring
- Addition to manual
V12 AccuClass-D Mono Amplifier: The V12 AccuClass-D amplifier design allows it to deliver massive power without correspondingly huge current draw.
Hood: The amplifier has a metal hood that flips up to reveal the control panel. The control panel consists of five buttons, Display, Mode, Enter, <, and >. These buttons are used to navigate the menu that includes all the adjustments on the amp (input level, crossover, EQ, time correction, phase, etc).
Verification Certificate: The amplifier comes with a certificate that informs you of the total RMS output of the particular amplifier. It lists the model number, serial number, test date, and the test conditions (voltage, impedance). The unit we opened measured 574.6 watts RMS into 2 ohms at 14.4 volts.
Display: The digital display can be switched between input voltage, current draw, and internal temperature in Celsius or Fahrenheit.
Sub-sonic Filter: The sub-sonic filter is used to filter out low frequencies that you cannot hear but can "rob" power from the amplifier. The crossover point is variable between 15Hz and 50Hz in 5Hz steps.
Built-in Variable Electronic Crossover: The built-in low-pass crossover is adjustable from 30 to 200Hz in 1/12 octave steps with a slope of 24dB/octave.
Parametric Equalizer: A fully adjustable parametric EQ is built into this amp. The center frequency is adjustable from 30 to 160Hz in 1/12 octave steps. The Q value of the EQ curve is selectable between 0.5, 1, 2, 3, 4, and 5. The EQ level is adjustable from -12dB to +12dB in 1dB steps.
Bass Compensation: The Bass Compensation circuit is used to enhance low-end bass definition.
Time Correction: Time correction allows you to time align this amp with others in the system. This is particularly useful to maximize SPL if there are multiple subs and sub amps. The adjustment range runs from 0-10ms in 0.1ms steps.
Phase: The phase is selectable between 0 and 180 degrees.
Multi Amp Installation: Because the above adjustments are all digital and discrete, two of these amplifiers can be used to power the two voice coils of a DVC woofer (technically this is true of any amp, but with analog adjustments an oscilloscope is needed to ensure the outputs are identical).
Amplifier ID: Alpine makes a Remote Amplifier Control Center (RACC) that will control up to eight V12 AccuClass-D amplifiers. For this reason each amp needs its own ID when more than one amp and the RACC are used.
Turn On Delay: The time it takes the amp to turn on is adjustable. This is useful for eliminating turn on thump.
Safe Mode: The Safe Mode turns off the power output of the amp while leaving the control functions active. This might be used as a valet function.
Memory: All the settings on the amp can be stored in memory for easy return to your preferred values.
Protection Circuitry: The protection circuitry guards against accidents and undesired operation. Included are Short circuit, Over-voltage, and Thermal overload.
Top of Amplifier: The control panel consists of five buttons, Display, Mode, Enter, <, and >. These buttons are used to navigate the menu that includes all the adjustments on the amp (input level, crossover, EQ, time correction, phase, etc).
Front of Amplifier:
- Battery (+12 V): gold-plated set-screw terminal that will accept up to 4 gauge wire
- Remote (turn-on): gold-plated screw terminal that will accept up to 10 gauge wire or a spade up to 0.355" wide
- GND (ground): gold-plated screw terminal that will accept up to 4 gauge wire
- Speaker Output: gold-plated screw terminals that will accept up to 8 gauge speaker wire or a spade up to 0.5" wide
- RCA Input: gold-plated RCA line input jacks
- RCA Output: gold-plated RCA line output jacks
- Controller: DIN plug for connection of remote controller
RMS Power Rating (measured at 14.4V):
- Into a 4-Ohm Load: 250 watts x 1
- Into a 2-Ohm Load: 500 watts x 1
RMS Power Rating (measured at 12.0V):
- Into a 4-Ohm Load: 200 watts x 1
- Into a 2-Ohm Load: 400 watts x 1
Note: Minimum impedance is 2 Ohms.
Our Product Research Team
At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.