Cerwin Vega VPSTX12 12" Powered Spare Tire Subwoofer

The Cerwin Vega VPSTX12 is a 12-inch powered subwoofer designed to install in a vehicle's spare-tire well. It adds low-frequency support without requiring a conventional trunk-mounted subwoofer enclosure. Its shallow, round form factor is intended for drivers who want to preserve usable cargo space.

This all-in-one system combines a 12-inch subwoofer, sealed enclosure, and integrated amplifier in one assembly. The amplifier is rated at 150 watts RMS and 600 watts maximum, with a 2-ohm final impedance. It is suited to filling in bass response for factory or aftermarket car-audio systems.

The VPSTX12 is specified for a 20 Hz to 150 Hz frequency response and includes an adjustable 50 Hz to 150 Hz low-pass filter. A variable bass boost and selectable phase setting help tailor its low-frequency output to the vehicle and system. A fixed 20 Hz subsonic filter is also included.

Low-level RCA and speaker-level input options allow the subwoofer to connect with different head-unit configurations. When speaker-level input is used, the unit has an automatic turn-on circuit if a switched 12-volt turn-on lead is unavailable. A wired remote bass knob is included for convenient level adjustment from the cabin.

The shallow spare-tire application is designed around a 14.2-inch outside diameter and 4.7-inch overall height. It can be mounted in spare tires oriented deep-side down, while some deep-side-up spare tires may need to be flipped over first. The supplied 8 mm and 10 mm mounting bolts support installation in many vehicle spare-tire wells.

Key Features

• Spare-Tire-Well Design: Uses the spare-tire area to help retain trunk and cargo space.
• Integrated Amplifier: Combines the amplifier and subwoofer in one compact powered assembly.
• 150W RMS Output: Provides a continuous-power rating suitable for bass reinforcement.
• Flexible Inputs: Supports RCA low-level and speaker-level source connections.
• Adjustable Low-Pass Filter: Lets you set the upper bass cutoff from 50 Hz to 150 Hz.
• Wired Bass Knob: Provides in-cabin adjustment of subwoofer level.

Design & Installation

The VPSTX12 uses a shallow sealed spare-tire enclosure with a cast-aluminum exterior and integrated heatsink. Its 12-inch driver uses a polypropylene cone, rubber surround, and ferrite magnet motor structure. The enclosure measures 14.2 inches by 14.2 inches by 4.7 inches, with a 12.6-inch mounting diameter.

Confirm spare-tire-well clearance, mounting-bolt fitment, and tire orientation before purchase. The unit accepts RCA low-level or speaker-level input, but the manufacturer instructs users not to connect both input types at the same time. A high-quality power kit is required separately; the manual specifies 8 AWG battery power wire and cautions against using CCA wiring kits.