About the MTX XTHUNDER125.4
Versatile amp for almost any system
Versatile amp for almost any system
If you're looking for high power for your car's system, look no further than the XTHUNDER125.4 amplifier from MTX. This X-Thunder Series 4-channel amp can drive your front and rear speakers with 90 watts RMS each, for big sound that'll overcome road noise and give your music some real impact. You can also set this amp up into 3-channel mode to run your front speakers with 90 watts each and a subwoofer with 250 watts RMS. Or, you can bridge both front and rear channels of the amp to drive a pair of subs with 250 watts each.
Controls for superior tone
In addition to the power available, the XTHUNDER125.4 features variable high- and low-pass filters to adapt the amp for best results in your system. The variable bass boost adds just the right amount of low-frequency oomph, whether you're running a subwoofer or not.
- 4-channel car amplifier
- 90 watts RMS x 4 at 4 ohms (125 watts RMS x 4 at 2 ohms)
- 250 watts RMS x 2 bridged at 4 ohms (4-ohm stable in bridged mode)
- frequency response: 20-20,000 Hz
- Class AB amp technology
- variable high- and low-pass filters (40-250 Hz, 12 dB/octave)
- variable bass boost (0-18 dB at 45 Hz)
- preamp and speaker-level inputs
- fuse rating: 30A x 2
- 8-gauge power and ground leads recommended wiring and hardware not included with amplifier
- 14-1/8"W x 2-1/16"H x 8-15/16"D
- warranty: 2 years
- Our 60-day money-back guarantee
- MFR # XThunder125.4
What's in the box:
- 4-Channel amplifier with two 30A ATC fuses installed
- 2mm Allen wrench
- 2.5mm Allen wrench
- 3mm Allen wrench
- 8" Speaker-level input harness (with an 8-pin Molex plug on one end)
- 4 Self-tapping screws (Length=3/4")
- Owner's Manual
More details on the MTX XTHUNDER125.4
Features & specs
|RMS Power Output (Watts x Channels)||
90 x 4 |
|Peak Power Output (Watts x Channels)||---|
|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||20-20000 Hz|
|THD at Rated RMS Power||1%|
|Signal to Noise Ratio||60 dB|
|Low-Pass Crossover Frequency||40-250 Hz|
|Low-Pass Slope (dB/octave)||12 dB/oct|
|High-Pass Crossover Frequency||40-250 Hz|
|High-Pass Slope (dB/octave)||12 dB/oct|
|Bass Boost||0-18 dB|
|Bass Boost Frequency||45 Hz|
|Speaker Level Inputs||Harness|
|Parts Warranty||2 Years|
|Labor Warranty||2 Years|
Class AB 4-channel Amplifier: The MTX XTHUNDER125.4 is designed to power four full-range speakers, or two speakers and a subwoofer. The amp's Class AB design and extruded aluminum top cover keeps the amplifier running cool.
Circuitry: MTX X-Thunder amplifiers feature dual-sided circuit boards with increased copper traces for maximum current transfer and to avoid power loss. Surface-mounted components increase durability and resistant to vibrations.
Power Output: The XTHUNDER125.4 produces 90 watts RMS x 4 at 4 ohms, or 125 watts x 4 at 2 ohms. You can bridge the rear channels to get 250 watts when connected to a 4 ohm load.
Protection Circuits: The XTHUNDER125.4 provides Thermal, Short circuit, and Over- and Under-voltage protection with an LED indicator.
Auto Turn-on: The amp features automatic turn-on circuitry which allows installation via high-level input without the use of a remote wire. When an audio signal is detected on the high-level input, the amplifier will turn itself on. The Remote Turn-on switch should be in the "Auto" position.
Input Level: The amplifier is divided into two sections for the front and rear channels. Each section has an Input Level control, which helps you match the amplifier's sensitivity to the signal voltage of the source unit. A small screwdriver is required to set the input level.
Crossovers: The XTHUNDER125.4 features separate 12 dB/octave crossovers for the front and rear channels. Each crossover is variable with a 40Hz to 200Hz cutoff frequency, and can be configured as High-pass, Low-pass, or bypassed (Full-range). A small screwdriver is required to adjust the cutoff frequency.
Bass Boost: The amplifier has separate bass boost circuits for the front and rear channels. The amount of boost is adjustable from 0-18dB at 45Hz.
Power/Ground/Turn-On Connections: The XTHUNDER125.4 features set-screw terminals for the Power, Ground and Remote turn-on lead. The terminals can be tightened/loosened with the supplied 3mm and 2.5mm Allen wrenches. The Power and Ground terminals will accommodate up to a 4 AWG wire (minimum of 8 AWG wire is recommended). An in-line fuse holder with an 80A fuse (or next highest available) should be placed on the power wire within 18" of the positive battery terminal. Typically, an 18 AWG turn-on lead is included with most amp wiring kits. If using the Speaker Level Input, no turn-on lead is needed.
RCA Inputs: The two pairs of RCA input jacks are for connecting source units with preamp outputs. The low-level input sensitivity range is 200mV to 5V. When using the RCA inputs, you should place the Remote Turn-on switch to the "EXT" position.
Speaker Level Input: The XTHUNDER125.4 comes with a 4-channel speaker level input harness, allowing you to connect a factory radio or a receiver with no preamp outputs. After splicing front and rear, left and right speaker wires to the speaker-level input harness, the harness plugs into the amplifier's Molex connection. When using the speaker-level inputs, the amp automatically turns on when it senses signal from the head unit, eliminating the need for a remote turn-on connection. In many cases, this feature will allow you to install the amplifier without removing your radio. The Remote Turn-on switch should be in the "Auto" position.
Speaker Connections: The amplifier is equipped with four pairs of speaker terminals for connecting four full-range speakers, or two speakers and one subwoofer (3-channel mode). The set-screw speaker terminals will accommodate 12 to 10 AWG speaker wire, and can be tightened/loosened with the supplied 2mm Allen wrench.
Remote: The amp has an RJ-25 jack for connecting the optional Electronic Bass Control.
Fuses: The amplifier is equipped with two 30-amp ATC-type fuses.