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Boston Acoustics GTA-704
4-channel car amplifier 70 watts RMS x 4
Item # 065GTA704 | MFR # GTA-704
This item is no longer available.
Our take on the Boston Acoustics GTA-704 by Crutchfield's Buck Pomerantz
Boston Acoustics takes much of the technology they developed for their top-of-the-line GT Reference amps, and uses it in their latest GTA Series amplifiers. The 4-channel GTA-704 amplifier puts out 70 watts RMS per channel plenty enough power to rock two sets of speakers or components. You can also drive a pair of subs with 250 watts RMS each in 2-channel mode, or bridge the rear channels to send 250 watts to a sub while the front channels run your full-range speakers. Boston Acoustics' Q-Tune technology lets you bump up your bass, whether you're running a subwoofer or not. The inputs feature special noise-cancellation circuitry that ensures clean reproduction of your music all the way through to your speakers.
The amp's Integral Mounting System puts the mounting holes in each corner of the frame, instead of using protruding tabs that waste space. You'll find all connections and adjustment controls recessed on one side of the amp, for a neat installation and easy adjustment. Variable high- and low-pass filters let you tune the amplified signal so your system can sound its best. An optional wired remote control gives you the power to tweak the bass level from the front seat.
great amp to power 4 Polk Audio DXi6500 6.5" Component Speaker System speakers, a bit of a snug fit under a 08 tundra passenger seat but will fit.
What's in the Box:
- 4-Channel amplifier
- Four 25-amp ATO fuses (two installed/two spare)
- Four 3/4" Self-tapping screws
- 3mm Allen wrench
- 2mm Allen wrench
- Two 12" Speaker input harnesses
- Owner's manual (English)
- Owner's manual (Spanish/ French)
- Warranty information
- 4-channel car amplifier
- 70 watts RMS x 4 at 4 ohms (125 watts RMS x 4 at 2 ohms)
- 250 watts RMS x 2 bridged output at 4 ohms (4-ohm stable in bridged mode)
- CEA-2006 compliant
- variable high-and low-pass filters (50-200 Hz, 12 dB/octave)
- Q-Tune technology switchable bass boost (6 dB at 45 Hz) on rear channels only
- optional wired remote subwoofer level control
- Symmetrical Signal Technology (SST) uses asymmetrical balanced inputs for noise cancellation
- frequency response: 10-50K Hz
- preamp and speaker-level inputs
- fuse rating: 25A x 2
- 8-gauge power and ground leads recommended wiring and hardware not included with amplifier
- 14-1/8"W x 2-3/8"H x 8-5/16"D
- warranty: 2 years
- Our 60-day money-back guarantee
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Features and Specs
|RMS Power Output (Watts x Channels)||
70 x 4
|Peak Power Output (Watts x Channels)||N/A|
|Power at 2 Ohms (Watts x Channels)||125 x 4|
|Bridged Power (Watts x Channels)||250 x 2|
|Minimum Impedance Bridged||4|
|Minimum Impedance Unbridged||2|
|Best Frequency Response||10-50000 Hz|
|THD at Rated RMS Power||1%|
|Signal to Noise Ratio||90 dB|
|Low-Pass Crossover Frequency||50-200 Hz|
|Low-Pass Slope (dB/octave)||12 dB/oct|
|High-Pass Crossover Frequency||50-200 Hz|
|High-Pass Slope (dB/octave)||12 dB/oct|
|Bass Boost||6 dB|
|Bass Boost Frequency||45 Hz|
|Speaker Level Inputs||Harness|
|Parts Warranty||2 Years|
|Labor Warranty||2 Years|
Multi-Channel Design: The Boston GTA 704 is a 4-channel amplifier, basically two independent 2-channel amplifiers built into one chassis. Either side can be bridged so it can be used as a 4-channel, 3-channel, or 2-channel amplifier. The amplifier is stable down to 2-ohms in stereo, and 4-ohms when bridged.
CEA 2006 Compliant: The GTA 704'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:
- Four-Channel (4-ohm): 70 watts x 4-channels into 4-ohms with no more than 1% THD+N
- Four-Channel (2-ohm): 125 watts x 4-channels into 2-ohms with no more than 1% THD+N
- Bridged (4-ohm): 250 watts x 2-channels into 4-ohms with no more than 1% THD+N
Controls and Terminals: All the controls and terminals are conveniently mounted on one side of the amp.
Gain: The amplifier's gain setting is adjusted using two independent rotary controls for the front and rear channels. The line-level input gain settings are continuously variable from 200 mV to 5.0 V; the speaker-level input gain settings are continuously variable from 400 mV to 10.0 V.
Crossover Switches: There are also independent crossovers for the front and rear channels; each can be set to HP (high pass), Off (full range), or LP (low-pass).
Crossover Frequency: You can independently select the crossover frequency for the front and rear channel crossovers; each is continuously variable from 50 to 200 Hz. The crossover slope is 12 dB/oct.
Q-Tune: Q-Tune bass boost can be applied to the rear channels; the boost is +6 dB at 45 Hz and can be turned off if you prefer.
Speaker-level Input: Front and rear speaker-level input harnesses (included) supply signal to the amp when the receiver has no RCA outputs.
Line-level Input: The front and rear amplifier sections have independent RCA input jacks.
GTA-RSL: RJ-14 port; connect an optional GTA-RSL remote level control (item number 065GTARSL, sold separately); the GTA-RSL is attached to the rear channels and only functions when the low-pass crossover is engaged.
Speaker Output: Four pair of set-screw terminals are provided for connecting the speakers; the terminals accept up to 10-gauge wire; the set screws are tightened/loosened with the supplied 2mm Allen wrench.
ATO Fuse: Two 25-amp ATO-type fuses are located between the speaker and power terminals.
Power/Remote: The power, ground, and remote wires connect to three set-screw terminals. Each terminal accepts up to 8-gauge wire and the set screws are tightened/loosened with the supplied 3mm Allen wrench.
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