SoundXtreme ST-2500-2 2-Channel Class AB Car Amplifier

The SoundXtreme ST-2500-2 is a 2-channel Class AB car audio amplifier designed for systems that need substantial output with adjustable crossover control. It can be used to power compatible full-range speakers or subwoofers, depending on system wiring and tuning. Its 2-ohm and 4-ohm operating capability gives installers flexibility when matching speakers to the amplifier.

This amplifier is suited to enthusiasts building a higher-output aftermarket audio system in a car, truck, RV, ATV, or similar 12-volt application. Separate high-pass and low-pass filter ranges help direct appropriate frequencies to the connected speakers. Variable gain adjustment also helps match the amplifier to the output level of the source unit.

The ST-2500-2 uses a Class AB MOSFET power supply design and is rated for up to 5,000 watts maximum output. Confirmed power figures are 2,500 watts per channel at 2 ohms and 1,250 watts per channel at 4 ohms, both specified at 1% THD. It is a stereo amplifier that can also be configured for bridgeable and tri-mode operation where the speaker setup supports it.

For signal management, the amplifier provides a continuously variable 12 dB/octave high-pass crossover from 80 Hz to 1.2 kHz and a low-pass crossover from 50 Hz to 250 Hz. Its rated frequency response is 10 Hz to 30 kHz, supporting subwoofer-focused and full-range system applications. A remote subwoofer level control is included for convenient level adjustment from the listening position.

The ST-2500-2 fits into an upgrade path for systems that need more external amplification than a factory or aftermarket receiver can provide. Chrome-plated RCA connections, variable gain, LED status indicators, soft start, and muting functions support practical integration into a 12-volt car audio installation. Proper power wiring, fusing, speaker impedance, and gain setup are important for dependable operation.

Key Features

• Two-Channel Class AB Design: Provides stereo amplification for compatible speakers or subwoofers.
• 2-Ohm Stable Operation: Supports compatible 2-ohm and 4-ohm speaker loads.
• Adjustable Crossovers: HPF and LPF controls help tailor frequency output.
• Remote Bass Level Control: Lets the listener adjust subwoofer level conveniently.
• Variable Gain Control: Helps match amplifier input level to the source unit.
• Status And Protection Indicators: LED lights provide at-a-glance operating feedback.

Design & Installation

The amplifier uses a metal chassis with a Class AB MOSFET PWM power supply architecture. Chrome-plated RCA and power/speaker terminal connections are specified, while soft-start and muting functions are included as part of its operating design. The chassis measures 9.5 inches wide, 2.5 inches high, and 24.3 inches deep.

Mount the amplifier securely in a ventilated location and use appropriately sized power, ground, speaker, and signal wiring for the installation. Set the gain only after the source unit and speakers are connected, then use the HPF or LPF controls to suit the speakers being powered. Verify final speaker impedance before wiring, as the amplifier is specified for 2-ohm and 4-ohm operation rather than 1-ohm operation.