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Boston Acoustics GT-2125

600W RMS GT Reference Series 2-Channel Amplifier

Discontinued
|

We apologize

This item has been discontinued

Boston Acoustics GT Reference Series Amplifiers

Boston Acoustics GT Reference amplifiers are perfect for just about any situation and any installation. The GT-2125 2-channel amplifier has a CEA-2006-A power rating of 125W x 2 channels @ 4 ohms, 200W x 2 channels @ 2 ohms, 400W x 1 channel bridged @ 4 ohms, and 600W x 1 channel bridged @ 2 ohms. All of these ratings give the amplifier unsurpassed versatility, whether you are amplifying a set of speakers or even a subwoofer. Q-Tune™ technology will combine your main speakers with the subwoofers, giving you bass up front and a whole new way of enjoying your music. The unique forced air cooling system allows for extreme heat dissipation and installation anywhere without the need to worry of thermal overload. Variable low and high crossovers combined with the Q-Control feature will give you complete control of all frequencies to better fine tune your audio system to better meet your personal preferences. GT Reference amplifiers provide unmatched technology and reliable power output, they are easy to install and are capable of stereo or mono operation with its DualMode™ feature. With all of its features and technologies GT Reference amplifiers are a great choice when selecting an amplifier.

Amplifier Features:

  • GT Reference Series 2-Channel Amplifier
  • RMS Power Rating(CEA-2006-A):
    • 4 ohms: 125 watts x 2 chan.
    • 2 ohms: 200 watts x 2 chan.
    • Bridged, 4 ohms: 400 watts x 1 chan.
    • Bridged, 2 ohms: 600 watts x 1 chan.
  • RMS Power Rating(12V):
    • 4 ohms: 95 watts x 2 chan.
    • Bridged, 2 ohms: 475 watts x 1 chan.
  • Remote bass level input (GT-RSL remote level control sold separately)
  • Red LED power badge and orange protect indicator
  • 2/1 channel operation
  • Adjustable mounting feet (mounting feet move along rails to allow the easiest installation)
  • Fully computer-controlled diagnostics system (continuously monitors amplifier in case of thermal overload, short circuits, or over voltage)
  • Q-Tune™ technology combines sophisticated crossover adjustments with Q-Control settings to seamlessly transition rear bass to the front sound stage
  • Uses a 40 amp ANL fuse
  • Heavy duty fan cooled aluminum alloy heatsink
  • Gold-plated RCA level inputs
  • Gold-plated screw terminals
  • Variable high-pass filter (20-350 Hz, 12 dB/octave)
  • Variable low-pass filter (50-350 Hz, 12 or 24 dB/octave)
  • Signal Voltage Input (200mV-8V)
  • Frequency response: 10-95,000 Hz
  • Dimensions: 13-1/4"L x 9"W x 2-3/8"H
  • 4-gauge power and ground wiring is required for installation. Contact us for information regarding a discount on select amplifier kits when purchased together with this amplifier.
  • 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.

125 watts x 2 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.

200 watts x 2 channels
RMS Power @ 1 ohm

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 1 ohm, 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.

Not Stable
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.

600 watts x 1 channels

Amplifier Specifications

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.

AB
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.
2
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.

600 watts
Maximum Input Gauge Size
This is the largest gauge wire that will fit into the power and ground terminals of this device. The lower the gauge number, the thicker the wire is. For example, a 4 gauge wire is thicker than an 8 gauge wire and thus has higher current carrying capacity. Always do your best to get this size wire to reduce the risk of damage to your components.
4 AWG
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.
2 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.
.03%
Speaker Level Inputs
Speaker level inputs are commonly referred to as high-level inputs and vice versa. This input type allows you to get your audio signal directly from the speaker wire in your vehicle, instead of using RCA cables. The advantage of this is factory integration, as most stock radios do not have RCA outputs to run amplifiers.
No
Preamp Outputs
Many amplifiers are equipped with RCA preamp outputs which pass the original music signal from the source to additional amplifiers. This is known as daisy chaining because the source connects to the first amp, and the first amp connects to the second amp, etc. The advantage to daisy chaining is you only need one 2-channel RCA cable to transfer the signal from the head-unit to the amplifier, and then one additional cable for each amp being daisy chained.
No
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.

20 - 350 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 - 350 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.
100 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
Fan Cooled
A great feature to have if an amp generates a large amount of heat. Cooling fans can help regulate the temperature to prevent the amp from overheating (burning).
Yes
Fuse Rating
The amperage and the number of fuse(s) an amp requires.
40A x 1 
CEA-2006 Compliant
Amplifiers that have been tested to meet specific standards. When a car amplifier meets these standards, you can be sure that it will be able to produce the amount of power specified by the official CEA-2006 rating. Usually, these rating consist of the following items:
  • RMS Power
  • Signal-to-Noise Ratio

This rating applies to both external car amplifiers, as well as the amplifiers inside of in-dash stereos.

Yes

Warranty and Return Policy

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

Summary of Customer Ratings & Reviews

Rating Distribution

5 Star
88%
4 Star
13%
3 Star
0%
2 Star
0%
1 Star
0%

Average Attribution Rating

Durability
4.5
Value
4.8
Features
4.6
Design
4.8
Usability
4.9

jocelyn

silver city, NM

Overall
Durability
Value
Features
Design
Usability

Great Amp

December 17, 2012

This amp is auwsome I have it with the Boston g1 dual sub box I also got from this site and sounds very crisp n clear with about 500 Watts. RMS on 13.75 volts very clean deep bass u can get the Boston G1 dual 12s with this amp, that's a great buy and combo definitely recommend Boston products as well as this site.

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Pascal

Canada

Overall
Durability
Value
Features
Design
Usability

Can't go wrong!

August 7, 2012

I'm using 4 of these to power 2 component units in my SUV (1 amp per door) and the power is mindblowing. Nice look, easy setup, good build quality. For the price, you just can't go wrong. I've put 3 stars for reliability because they're brand new and i don't know how reliable they will be.

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Parker

Fargo ND

Overall
Durability
Value
Features
Design
Usability

recommended for running woofers also

July 28, 2012

Great amp. Boston acoustic, need I say more? Running 2 fifteen inch Boston acoustic g2s on it 300 rms a piece @ 2 ohm bridge and it sounds so nice! Crisp, pure, clean hard low thumping bass. It does get warm at 2 ohm bridge but the heat sink and cooling fan does do there jobs leaving it warm not hot... Frequency reach is unbelievable. Anything from rock, screamo, country, hip hop, dub step everything it plays perfect. If I could id keep this system for life

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andrew

oakley, CA

Overall
Durability
Value
Features
Design
Usability

dont bother buying another amp

June 27, 2012

this amp is incredible boston acoustics has always been a choice of mine best bang for buck ever

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Ty

Livonia, MI

Overall
Durability
Value
Features
Design
Usability

Made my speakers ear piercing

March 14, 2012

Bought this amp when it was $300 and it is worth every penny then, now I see it listed at for a little higher an I'm a bit jealous now. If you're considering this amp I don't know if you can find a better amp for the price. I have both sets of my infinity perfect 6.1 speakers hooked up to this guy and they absolutely scream with clarity. For those of you who have the infinity perfect 6.1 speaker and are having impedance issues with the speakers driving the amp into protect mode, if you do enough research you'll see that some of these speakers have impedance issues, maybe from the crossovers. But i have not had an issues with my speakers on this amp. I have each set wired in series so the amp is seeing 8 ohms a channel, but since there are these impedance issues, or whatever you want to call it, i dont know what the actual resistance is, but i know the amp has never went into protect and i haven't blown a speaker. Have the gain at 4V and had to turn the tweeter setting to -4dB. Hope that helps someone with the infinity perfect 6.1 impedance/clipping problem. I tried the Infinity Reference 475a and rockford amps and they all went into protect unless i wired in series and kept the gain really low. This amp should not have a problem though

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LT

lagrange GA

Overall
Durability
Value
Features
Design
Usability

OK

October 16, 2011

This is an ok amp. Running a set of dls reference m6 with it. Doesn't get hot at all running at about 3 ohms. Don't know if i would use on subs though. deff not 2 ohms bridged gets kinda warm as is but does come with a fan right by the heat sink on the back.

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Grant

Canada

Overall
Durability
Value
Features
Design
Usability

Awesome amp!

January 21, 2011

I bought this and hooked it up with an 12" Alpine Type R. WOW. This thing puts out unreal power! Better than a Alpine 500 Amp with 2 type S's.

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car audio retailer.

billings mt.

Overall
Durability
Value
Features
Design
Usability

the best there is!

October 24, 2010

Boston gt series amplifiers are the best. Just compare the thd- distortion level. Also they have by far the widest range of frequency reproduction of any amp I have ever seen! And that is all you need for a crystal-clear extremely loud system. Buy these amps for subs and interior. U won't regret it.

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Accessory Tools and Products

Accessories added

NVX XKIT42 100% OFC True 4 Gauge Wiring Kit with RCA Cables and Speaker Wire

The reviews speak for themselves, this is awesome wire with everything you need!

Your Price $89.99

Stinger SK4641 4 Gauge Wiring Kit

Get a high quality amp kit from Stinger to get the most from your new amp!

Your Price $64.99

Belva BAK42 4 Gauge Amplifier Installation Kit

Great amps need great wire at a great price. This amp kit has everything you need!

Your Price $29.99

NVX XBG3PK 1/0 Gauge OFC Big 3 Upgrade Kit

Comes with everything you need to upgrade your power and ground wire.

Your Price $79.99

Kicker Big 3 Package 1/0 Gauge Big 3 Upgrade Kit

Get all you need including wire cutters to upgrade your power and ground wire.

Your Price $149.99

Belva BBG3KT CCA 1/0 Gauge Big Three Kit

Features everything needed to upgrade factory power and ground wire.

Your Price $39.99

StreetWires FB4

4 AWG / 4 Gauge Firewall Bushing

Your Price $6.95

NVX XDBU4 - Top of the Line!

Distribution Block with Two 1/0 or 4 AWG Inputs and Four 4 or 8 AWG Outputs

Your Price $17.99

Professional Installation for your Car Power Amplifier

Covers labor charges through our professional installer network.

Your Price $89.99

NVX XIV25 V-Series 2-Channel RCA Cable

16.4 ft 2-Channel RCA Audio Interconnect Cable with Twisted Pair Construction

Your Price $11.99

Kicker Q-Series RCA Interconnect Cable

16.5 ft. of 2-Channel Interconnects with twisted pair conductors, K-cut gold plated contacts, and hyper-flex technology for easy installation!

Your Price $32.95

NVX XIX25 X-Series Interconnect Cable

16.4 ft. of 4-Channel X-Series RCA Cable with Dual Twisted Pair Hyper-Flex Technology

Your Price $26.99

NVX XWS1225 12 AWG Speaker Wire

25 ft. of True 12 Gauge 100% Copper EnvyFlex Speaker Cable/Wire

Your Price $39.99

NVX XWS1625 16 AWG Speaker Wire

25 ft. of True 16 Gauge 100% Copper EnvyFlex Speaker Cable/Wire

Your Price $13.99

Belva BBSW127 12 AWG Speaker Wire

12 Gauge 7 Meter (23 Ft) Speaker Wire (CCA)

Your Price $14.99

Belva BBSW167 16 AWG Speaker Wire

16 Gauge 7 Meter (23 Ft) Speaker Wire (CCA)

Your Price $12.99

Scosche SPL Meter SPL1000F

Handheld boomSTICK measures your SPL range from 60 to 135 dB

Your Price $21.99

AutoSound 2000 CD-102

High Frequency Test CD specifically designed for the set-up and evaluation of sound system imaging and placement.

Your Price $11.99

AutoSound 2000 CD-104

Audiophile reference series test disc for evaluation of all audio components.

Your Price $11.99

Product Summary

Manufacturer

Model Number

GT-2125

UPC

690283474638

Weight

9.00lbs

Internal SKU

gt2125

Internal Product ID

17785

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: Boston Acoustics GT-2125