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Boston Acoustics GT-2125

600W RMS GT Reference Series 2-Channel Amplifier

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GT Series 2-Channel Reference Amplifier • 125W x 2 Chan. @ 4 Ohm • 200W x 2 Chan. @ 2 Ohm • Fully Computer-Controlled Diagnostics System • Q-Tune™ Technology • Fan Cooled Aluminum Alloy Heatsink •

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Product Highlights


GT Series 2-Channel Reference Amplifier • 125W x 2 Chan. @ 4 Ohm • 200W x 2 Chan. @ 2 Ohm • Fully Computer-Controlled Diagnostics System • Q-Tune™ Technology • Fan Cooled Aluminum Alloy Heatsink •

Description


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 ohm: 125 watts x 2 chan.
    • 2 ohm: 200 watts x 2 chan.
    • Bridged, 4 ohm: 400 watts x 1 chan.
    • Bridged, 2 ohm: 600 watts x 1 chan.
  • RMS Power Rating(12V):
    • 4 ohm: 95 watts x 2 chan.
    • Bridged, 2 ohm: 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

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Specifications & Details


Power Specifications - Full Range Channels
RMS Power @ 4 ohms
125 watts x 2 channel
RMS Power @ 2 ohms
200 watts x 2 channel
RMS Power @ 1 ohm
Not Stable
Bridged RMS Power
600 watts x 1 channel
Amplifier Specifications
Amplifier Class
A/B
Number of Channels
2-Channel
Total RMS Power Output
600 watts
Maximum Input Gauge Size
4 AWG
Minimum Impedance Unbridged
2 ohm
Minimum Impedance Bridged
2 ohms
THD at Rated RMS Power
.03%
Speaker Level Inputs
No
Preamp Outputs
No
Built-in Crossover
Low-Pass (LP)
High-Pass (HP)
High-Pass Crossover Frequency
20 - 350 Hz
Low-Pass Crossover Frequency
50 - 350 Hz
Signal-to-Noise Ratio
100 dB
Remote bass/level controller
Yes
Fuse Rating
40A x 1 
Warranty and Return Policy
Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider
Manufacturer

Item Details


Manufacturer:

Model Number:

GT-2125

Weight:

9.00lbs

Internal SKU:

gt2125

Internal Product ID:

17785

Product and How-to Videos


Customer Ratings & Reviews


Boston Acoustics GT-2125 thumbnail image

5 star
89%
4 star
11%
3 star
0%
2 star
0%
1 star
0%



Durability
4.6
Value
4.8
Features
4.7
Design
4.8
Usability
4.9

Customer Reviews

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dont bother buying another amp

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

By andrew on June 27, 2012

37 found this helpful


the best there is!

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.

By car audio retailer. on October 24, 2010

38 found this helpful


Awesome amp!

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.

By Grant on January 21, 2011

36 found this helpful


Can't go wrong!

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.

By Pascal on August 7, 2012

35 found this helpful


recommended for running woofers also

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

By Parker on July 28, 2012

36 found this helpful


OK

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.

By LT on October 16, 2011

35 found this helpful


Made my speakers ear piercing

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

By Ty on March 14, 2012

34 found this helpful


Great Amp

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.

By jocelyn on December 17, 2012

33 found this helpful


Sounded great

Used this amp on infinity kappa 6.5 front doors speakers . Was a good choice

By Johnnie on July 28, 2025 Checkmark Icon Verified purchase

5 found this helpful



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