JBL JBLSTAGEGT50011AM Mono Class-D Subwoofer Amplifier

The JBL Stage GT 50011 is a mono Class-D amplifier designed to power a car subwoofer system. It provides 500 watts RMS at 2 ohms or 300 watts RMS at 4 ohms, giving installers a focused amplifier option for adding low-frequency output without powering the full speaker system. Its compact chassis helps make it practical for vehicle installations where available mounting space is limited.

This amplifier is intended for shoppers building a dedicated subwoofer upgrade, whether they are retaining a factory radio or using an aftermarket head unit. Speaker-level and low-level input sensitivity ranges support integration with a variety of source units. OEM Load Detect compatibility is included for factory audio systems that need a specific resistance to operate properly.

The Stage GT 50011 is tuned for bass-duty operation, with a 10Hz–320Hz frequency response and a variable low-pass filter. A variable phase control from 0° to 180° can help align subwoofer output with the rest of the system. The adjustable bass EQ allows the installer to tailor boost level, center frequency, and width to the vehicle and enclosure.

Its Class-D design is paired with protection circuitry for DC, overvoltage, undervoltage, overcurrent, and overtemperature conditions. The amplifier operates across a 9V–16V range and is designed for use in vehicles with start/stop systems. A wired remote bass control is included for making bass-level adjustments from the front seat.

The Stage GT 50011 fits naturally into a system using a single 2-ohm or 4-ohm subwoofer load that matches its rated output. It can be used with RCA preamp outputs or with the supplied high-level input cable when connecting to compatible speaker-level signals. Proper power wiring, grounding, fuse protection, enclosure selection, and gain setup remain essential for reliable system performance.

Key Features

• Mono Class-D Design: Delivers dedicated power for a single subwoofer channel in a compact format.
• 500W RMS at 2 Ohms: Supplies rated continuous power for a properly matched 2-ohm subwoofer load.
• Variable Low-Pass Filter: Adjusts from 32Hz to 320Hz to blend subwoofer output with the main speakers.
• Adjustable Bass EQ: Provides variable boost level, frequency, and width for system-specific bass tuning.
• Factory-Radio Integration: Supports speaker-level inputs and OEM Load Detect compatibility for many factory systems.
• Wired Bass Remote: Lets the driver adjust bass level from the listening position.

Design & Installation

The amplifier uses a smooth bead-blast anodized extruded aluminum body with angular end caps and a glossy JBL logo. Its compact 9-23/32-inch-wide chassis measures under 2 inches tall, helping it fit in many vehicle mounting locations. Built-in protection monitoring helps safeguard the amplifier against several electrical and thermal fault conditions.

Install the amplifier in a dry, ventilated location where cooling is not blocked, and use the manufacturer-recommended 4-gauge power wiring. Match the connected subwoofer system to a 2-ohm or 4-ohm load, then set the input level, low-pass filter, phase, and bass EQ conservatively during final tuning. The supplied high-level input cable can be useful with factory radios, while RCA inputs can be used with a compatible aftermarket source unit.