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MB Quart MA1-740.5

740W 5-Channel Full Range M-Line Class D Compact Marine Ready Amplifier

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MB Quart MA1-740.5

740W 5-Channel Full Range M-Line Class D Compact Marine Ready Amplifier

$239.99

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General Features:

  • 5-Channel Full Range Class D Compact Marine Amplifier
  • Channel 1-4 RMS Power Rating:
    • 4 ohms: 75 watts x 4 chan.
    • 2 ohms: 110 watts x 4 chan.
    • Bridged, 4 ohms: 220 watts x 2 chan.
  • Subwoofer Channel RMS Power Rating:
    • 4 ohms: 200 watts x 1 chan.
    • 2 ohms: 300 watts x 1 chan.
    • Total RMS power output: 740 watts
    • New Marinized Design for Marine Application
    • Wired remote level control included
    • Added conformal coating and stainless hardware
    • Perfect for marine or powersports applications
    • Frequency Response: 10 - 20,000 Hz
    • Signal To Noise Ratio: 90 dB
    • THD: 0.02%
    • Variable Hi-Pass: 50- 3,000 Hz , 24 dB/octave
    • Variable Low-Pass, Chan 3 & 4: 50 - 3,000 Hz , 24 dB/octave
    • 45 Hz Bass Boost: 0 - 12 dB
    • Fuse Rating: 40A x 2
    • Dimensions (L X H X W): 10.24" x 6.50" x 1.97"
    • 4 gauge power and ground wiring is recommended for installation. Contact us for information regarding a discount on select amplifier kits from our website when purchased together with this amplifier.
    • Dimensions: "W x "L x "H
    • Authorized Internet Dealer
    • 1-year Manufacturer's Warranty

Power Specifications - Full Range Channels

RMS Power @ 4 ohms

The RMS power rating is the measure of continuous power that an amplifier can output, or a speaker can handle. It is the most accurate depiction of real, continuous power that the industry has so far.

If the final impedance of your speakers or subwoofers equals 4 ohms, this is how much power this amplifier will supply at that ohm level. The higher the RMS wattage, the more clean and loud your music will sound.

75 watts x 4 channels
RMS Power @ 2 ohms

The RMS power rating is the measure of continuous power that an amplifier can output, or a speaker can handle. It is the most accurate depiction of real, continuous power that the industry has so far.

If the final impedance of your speakers or subwoofers equals 2 ohms, this is how much power this amplifier will supply at that ohm level. The higher the RMS wattage, the more clean and loud your music will sound.

110 watts x 4 channels
Bridged RMS Power

Bridging refers to combining two channels on an amplifier to create one channel with double the voltage and an increased power output. A 2-channel amplifier will bridge down to 1-channel and a 4-channel amplifier can bridge to create 2-channels. An amplifier is most commonly bridged to drive a subwoofer.

Remember, once you bridge two channels down to one its final impedance will be 4 ohms unless otherwise specified. This rating lists the RMS power created once an amplifier is bridged.

220 watts x 2 channels

Power Specifications - Subwoofer Channel

RMS Power @ 4 ohms
The RMS power rating is the measure of continuous power that an amplifier can output, or a speaker can handle. It is the most accurate depiction of real, continuous power that the industry has so far. If the final impedance of your speaker(s) or subwoofer(s) equals 4 ohms, this is how much power this amplifier will supply at that ohm level. The higher the RMS wattage, the more clean and loud your music will sound. The 5th channel on these particular amplifiers are usually dedicated for driving subwoofers.
200 watts x 1 channels
RMS Power @ 2 ohms
The RMS power rating is the measure of continuous power that an amplifier can output, or a speaker can handle. It is the most accurate depiction of real, continuous power that the industry has so far. If the final impedance of your speaker(s) or subwoofer(s) equals 2 ohms, this is how much power this amplifier will supply at that ohm level. The higher the RMS wattage, the more clean and loud your music will sound. The 5th channel on these particular amplifiers are usually dedicated for driving subwoofers.
300 watts x 1 channels

Amplifier Specifications

Marine Certified
Marine certified means that the unit has been designed and manufactured with a marine use in mind. It will withstand the harsh conditions that come from marine use. Generally, they are treated against UV rays and treated with special protective coatings.
Yes
Amplifier Class

An amplifier increases the power of the signal being fed to it by taking energy from its power supply and matching the signal but increasing its amplitude. Amplifiers use many different methods for converting these electrical signals and have been categorized into classes.

Class A/B: Greater than 50% of the input signal is amplified while the other percentage is “off”. These amplifiers have a small amount of current flowing through the output transistors all the time which almost eliminates crossover distortion. Class A/B has great sound quality but is not as efficient as class D. These amps are most commonly used to drive speakers.

Class D: Also known as switching amplifiers, class D amps have output transistors that are completely turned “on” or “off”. This means that when the transistors are on, there is almost no voltage across them but when they are off there is significant voltage but no current flowing through it which makes these amplifiers very efficient at the cost of sound quality. These amps are most commonly used to drive subwoofers.

Other Classes: You may see classes such as GH, bD, X, FD, etc. by some manufactures. These amplifiers tend to be either class A/B, D or a hybrid of the two but with improvements to their designs that can make them more efficient or offer better sound quality.

D
Number of Channels
Each channel on an amplifier will power one speaker using a positive and negative cable. There are various types of amplifiers, each designed to power a certain number of speakers. Monoblock amplifiers, also known as single channel, are designed to power one or more subwoofers. These amplifiers often have very high power ratings. On the other hand, multi-channel amplifiers power multiple speakers, usually at lower power ratings. 2-Channel and 4-Channel amplifiers can power car speakers or low powered subwoofers. Occasionally you might see a 5 or 6-channel amplifier that can power speakers and subwoofers at the same time. The most common setup is a monoblock amp to run subwoofers and a 4-channel amp to run door speakers. Check out our Knowledge Base for more information.
5
Total RMS Power Output
Total RMS power is measured by multiplying RMS power per channel by the number of channels, and is calculated at the lowest level of operating impedance.

RMS power is the amount of continuous power, measured in watts, that an amplifier produces is called RMS power. The higher the RMS figure, the louder and cleaner your music sounds.

The RMS output figure is much more accurate than the peak rating when comparing products.

740 watts
Minimum Impedance Unbridged
The lowest impedance the amplifier will handle when it is not bridged.
2 ohms
Minimum Impedance Bridged
The lowest impedance the amplifier will handle when it is bridged.
4 ohms
THD at Rated RMS Power
The amount of change in harmonic content of the signal as it is amplified. A lower figure indicates less change and a more accurate amp. THD below 0.10% is inaudible.
0.02%
Built-in Crossover

A crossover is a type of filtering system that permits only certain frequencies to play. A Low-Pass (LP) crossover allows only frequencies below its setting to get through which is good in the case of some subwoofers. A High-Pass(HP) filter allows frequencies above its setting to pass through, this is normally used on speakers.

When a crossover is set to FULL it means no filtering is added and the full frequency spectrum is allowed through the amplifier. Filtering is important because feeding a speaker frequencies it cannot reproduce effectively creates distortion.

Low-Pass (LP)
High-Pass (HP)
High-Pass Crossover Frequency
The high-pass crossover frequency can be a fixed crossover point or a variable crossover range. A variable high-pass crossover allows you to select a specific crossover point which allows frequencies above the set crossover point to pass, while making frequencies below the set point gently or harshly roll-off, depending on the steepness of the slope.

The steepness of the roll-off slope is measured in dB/octave and refers to the rate of attenuation (lowering of volume) outside their pass bands.

50 - 3,000 Hz
Low-Pass Crossover Frequency
The low-pass crossover frequency is typically used for subwoofers. It can be a fixed crossover point or a variable crossover range. A variable low-pass crossover allows you to select a specific crossover point which allows frequencies below the set crossover point to pass, while making frequencies above the set point gently or harshly roll-off, depending on the steepness of the slope.

The steepness of the roll-off slope is measured in dB/octave and refers to the rate of attenuation (lowering of volume) outside their pass bands.

50 - 3,000 Hz
Signal-to-Noise Ratio
This spec compares the strength of the signal to the level of background noise. A higher value indicates less background noise.
>90 dB
Bass Boost
The objective of the bass boost is to get more kick out of your subwoofer. It is a circuit that emphasizes the lower frequencies at a given point. The bass boost should always be set first before setting the gain. This feature is known for destroying subwoofers and is commonly used incorrectly, so be cautious.
0 - 12 dB
Bass/Gain Remote
If the amp comes with a bass/gain remote you will be able to control the level of your bass from your dashboard. Typically bass remotes also include a 16-20 ft. wire for installation.
Yes
Fuse Rating
The amperage and the number of fuse(s) an amp requires.
40A x 2 

Warranty and Return Policy

Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider
Manufacturer

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Product Summary

Manufacturer

Model Number

MA1-740.5

UPC

806576223511

Weight

8.10lbs

Internal SKU

ma17405

Internal Product ID

94850

Sonic Electronix Wiring Guide

Wiring Diagram Legend

Warning: The image depicted shows the resistance change when wiring multiple subwoofer terminals. Please refer to your subwoofer's owner's manual for the proper wiring of its terminals. Sonic Electronix, Inc. is not responsible for damage caused to your audio system or vehicle due to improper installation. Please call tech support at 1-877-289-7664 if you require additional assistance.

Product Name: MB Quart MA1-740.5