STX Audio STX850W Digital Bass Processor with Dash Remote

The STX Audio STX850W is a car-audio bass processor designed to restore and shape low-frequency information in an RCA-based signal path. It is intended for systems that need more adjustment than a conventional bass boost control can provide. The processor lets installers and listeners tune bass character for the vehicle, subwoofer system, and source material.

A dedicated bass restoration circuit is used to enhance low-frequency content that may be reduced in recordings or playback sources. The SWEEP control selects the center frequency from 27Hz to 63Hz, while the WIDE control adjusts the range affected by the processing. A separate subwoofer level control provides an additional way to set bass output.

The STX850W is specified with a 10Hz to 35kHz frequency response, 133dB signal-to-noise ratio, and 0.0025% total harmonic distortion. These published figures describe a processor built to integrate into a full-range car-audio signal chain while focusing its adjustment capability on bass. Balanced RCA inputs are designed to help manage noise in automotive electrical environments.

Its RCA inputs accept up to 15V RMS and use a 10 kOhm input impedance. The unit is specified for more than 62dB of noise rejection and can deliver up to 13.2V peak through 150-ohm RCA outputs. This makes it suited to systems using an aftermarket source unit, external amplifiers, or both.

A dash-mount remote is included for bass-level adjustment from the front of the vehicle. The remote has an LED indicator and a PFM subsonic filter switch for reducing very low frequencies outside the intended operating range of the system. The processor operates from a 12V DC automotive electrical system and draws 150mA.

Key Features

• Bass Restoration Circuit: Enhances low-frequency information in the audio signal.
• Adjustable Sweep: Selects bass center frequency from 27Hz to 63Hz.
• Wide Control: Adjusts the range affected by bass processing.
• Balanced RCA Inputs: Supports up to 15V RMS input signals.
• Dash-Mount Remote: Provides accessible bass-level adjustment and LED indication.
• PFM Filter Switch: Reduces unnecessary subsonic low-frequency content.

Design & Installation

The STX850W uses a separate processor-and-dash-remote layout, allowing the main unit to be placed in the audio system while the level control remains accessible to the driver. Specific enclosure materials are not published. Its design centers on RCA signal connections, front-panel adjustment controls, and a remote-mounted bass control.

Install the processor in an RCA signal path between the source unit and the applicable amplifier input, using its balanced RCA inputs and RCA outputs. Connect it to a 12V DC vehicle electrical supply within its specified 11V to 16V operating range, then set SWEEP, WIDE, subwoofer level, and the PFM switch to suit the subwoofer system. Professional installation is recommended when integrating the unit with factory audio electronics or high-output aftermarket equipment.