STX Audio STX-654 6.5" 4-Way Coaxial Speakers

The STX Audio STX-654 is a 6.5-inch, 4-way coaxial speaker system designed for replacing compatible factory car speakers. Its coaxial format combines multiple speaker elements into a single mounting location, helping retain a straightforward door- or panel-speaker upgrade path. The system is rated at 4 ohms per speaker for use in common automotive audio applications.

This speaker set is intended for drivers who want to refresh aging factory speakers or build a basic full-range system without adding separate component speaker locations. It can be operated from a factory head unit or paired with a multichannel amplifier. With 90 watts RMS rated per speaker, it offers a practical power-handling match for moderate aftermarket amplification.

The STX-654 uses a 4-way full-range design to cover a broad listening range from a compact 6.5-inch format. Its listed 60 Hz to 20 kHz frequency response is suited to reproducing much of the vocal, instrument, and high-frequency content in a vehicle audio system. Dedicated subwoofers may still be useful in systems that need stronger low-bass output.

A silk-dome tweeter is integrated with the woofer assembly, while the woofer is listed with a polypropylene construction. This integrated arrangement keeps the high-frequency driver aligned with the main speaker location and avoids the need to mount a separate tweeter. A moisture-resistant rubber surround is also specified for the speaker design.

For installation, the STX-654 is built around an anti-resonant stamped-steel basket and uses spade speaker terminals. Its listed 2-7/8-inch mounting depth should be checked against available clearance behind the intended mounting panel. It can serve as a direct-size replacement where a vehicle accepts 6.5-inch speakers, subject to verifying vehicle-specific cutout, mounting-hole, and depth requirements.

Key Features

• 6.5-Inch Coaxial Format: Fits applications designed for compatible 6.5-inch car speakers.
• 4-Way Full-Range Design: Combines multiple speaker elements in one assembly.
• 90W RMS Per Speaker: Supports moderate continuous amplifier power.
• 4-Ohm Impedance: Matches common automotive speaker wiring configurations.
• Silk-Dome Tweeter: Adds dedicated high-frequency reproduction within the speaker.
• Stamped-Steel Basket: Provides a rigid mounting structure for installation.

Design & Installation

The STX-654 combines a polypropylene woofer and silk-dome tweeter in a single coaxial assembly. It is specified with a moisture-resistant rubber surround, anti-resonant stamped-steel basket, 3-1/8-inch magnet, and 2-3/8-inch coil. Spade speaker terminals are provided for speaker-wire connection.

Confirm that the vehicle accepts 6.5-inch speakers and has at least 2-7/8 inches of usable mounting depth before installation. These speakers can be connected to a compatible factory head unit or a multichannel amplifier, with 4-ohm speaker-channel compatibility and appropriate power matching. Mounting hardware, adapters, and wiring accessories are not confirmed in the available product information.