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AMPLIFIERS

1.Fuses- For convenience, all amplifiers utilize ATC type fuses. For continued protection in the event that a fuse blows, replace the fuse only with the same value.

Caution - The power fuses on the amp are for protecting the amp against overdrive. To protect the vehicle’s electrical system, an additional fuse is required within 18" of the battery on the 12V+ cable.

Thunder4250D - 20A x 2

Thunder6500D - 25A x 3

Thunder81000D - 150 Amps (not supplied)

2.Power Terminal – This is the main power input for the amplifier and must be connected direct- ly to the positive terminal of the car battery for the amplifier to operate properly. See the chart below for recommended cable sizes for each amplifier. Use caution when running this cable through the car. Try to avoid the input RCA cables, antenna cabling, or other sensitive equipment as the large amount of current flowing through this cable can induce noise into your system. It is also very important to have a tight connection to ensure maximum performance.

Thunder4250D – 6-8 Gauge

Thunder6500D – 4-6 Gauge

Thunder81000D – 1/0 Gauge only

3.Ground Terminal – A good quality ground is required for your Thunder Amplifier to operate at peak performance. A short length of cable the same gauge as your power cable should be used to attach the ground terminal directly to the chassis of the car. Always scrape or sand any paint- ed surfaces to expose bare metal where the ground wire will attach.

4.Remote Terminal – All Thunder Amplifiers can be turned on by applying 12 volts to this termi- nal. Typically this voltage is supplied by a wire from the source unit marked “remote” or “electric antenna”.

5.Speaker Terminals – As shown in the wiring diagrams, be sure to observe speaker polarity through the system. Failing to wire the speakers in proper phase could result in a loss of bass response and/or poor overall sound quality. Caution: Thunder amplifiers are not recommended for loads below 2 ohms stereo or 4 ohms bridged.

6.Power LED (top of heatsink)- A lighted LED indicates that power has been applied to the amplifier. +12V from the battery to the +BATT terminal (#10) and +12V from a switched ignition or remote lead from a head unit. An unlighted LED indicates power has been removed or the amplifier has overheated. In the case of the overheat condition, the amplifier will turn back on after it cools down.

Output Panel Layout
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Thunder4250D, Thunder6500D, Thunder81000D specifications

MTX Audio has long been a dominant player in the car audio industry, and their Thunder series amplifiers, including the Thunder81000D, Thunder6500D, and Thunder4250D, exemplify the brand's commitment to delivering exceptional sound quality, innovative technology, and robust performance. Each model is designed to cater to different audio needs and vehicle setups, providing powerful solutions for car audio enthusiasts.

The Thunder81000D is a powerhouse amplifier that boasts an impressive output of 1000 watts RMS at 1 ohm. This model is particularly engineered for subwoofer applications, allowing users to connect multiple subwoofers without compromising sound quality. Featuring MTX Audio's proprietary technology, such as the Advanced Thermal Protection circuit, the Thunder81000D ensures that it remains cool even during extended use. Additionally, it includes a variable low-pass filter, making it easier for users to tailor the sound to their preferences.

The Thunder6500D is another solid option, rated at 650 watts RMS at 1 ohm. This amplifier is known for its robustness and efficiency, making it an excellent choice for mid-range and entry-level audio systems. Featuring a compact design, the Thunder6500D is designed for easy installation in tighter spaces without sacrificing performance. It also includes a bass boost feature, allowing users to enhance low frequencies for a more impactful listening experience. Furthermore, the inclusion of high- and low-level inputs offers versatility for different audio setups.

Finally, the Thunder4250D serves as the ideal solution for those looking for a 4-channel amplifier capable of delivering 250 watts RMS at 2 ohms. This model is perfect for powering full-range speakers or coaxial setups. The Thunder4250D incorporates a 12dB/octave high-pass and low-pass filter, enabling precise sound shaping. With a rugged construction and high-quality components, this amplifier delivers not only power but longevity, ensuring reliable performance over time.

In summary, the MTX Audio Thunder series amplifiers, including the Thunder81000D, Thunder6500D, and Thunder4250D, combine powerful output, innovative technology, and thoughtful design to provide exceptional audio performance. Whether you’re building a full-fledged sound system or enhancing your factory setup, these amplifiers offer the flexibility and power needed to achieve the ultimate listening experience. With their ability to drive subwoofers, full-range speakers, and everything in between, MTX Audio’s Thunder amplifiers are a compelling choice for any car audio enthusiast.

MTX Audio Thunder6500D, Thunder81000D, Thunder4250D owner manual ❷ ❹ ❸

Models: Thunder4250D Thunder6500D Thunder81000D

Thunder81000D - 150 Amps (not supplied)

Thunder4250D, Thunder6500D, Thunder81000D specifications