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A second-generation Stage GT Series 2-channel Class D car amplifier from JBL, the Stage GT80021 delivers 80W RMS at 4Ω and 130W RMS at 2Ω per channel, or 260W RMS bridged at 4Ω (800W peak), with an OEM Load Detect System for seamless factory integration, signal sensing remote turn-on, variable highpass filter (32-320Hz), variable lowpass filter (32-320Hz), variable bass boost (0-12dB), high-level and low-level inputs, Start-Stop vehicle compatibility, and comprehensive protection circuitry in a compact housing.
The JBL Stage GT80021 is a 2Ω stable 2-channel Class D amplifier from the second-generation JBL Stage GT series, engineered to deliver reliable power with minimum heat generation in a compact footprint. The high-efficiency Class D output stage delivers 80W RMS at 4Ω and 130W RMS at 2Ω in stereo, or 260W RMS bridged into 4Ω for dedicated subwoofer applications, with a total peak power of 800W.
The versatile dual-channel architecture provides complete system flexibility: operate as a stereo amplifier for a pair of door speakers at 80W per channel, or bridge the two channels to drive a subwoofer at 260W RMS into 4Ω. The OEM Load Detect System ensures seamless compatibility with both factory and aftermarket head units without interfering with the vehicle power management system. Start-Stop engine system compatibility maintains consistent audio output and battery efficiency during momentary engine stops. The signal sensing remote turn-on eliminates the need for a dedicated remote wire in many factory integration scenarios.
The onboard crossover provides a variable highpass filter (32-320Hz), variable lowpass filter (32-320Hz), and variable bass boost (0-12dB) for precise signal tuning to match specific speaker configurations and vehicle acoustics. Both low-level RCA inputs (0.2-5V) and high-level speaker-level inputs (1-25V) accommodate virtually any audio source. Protection circuitry covers direct current, overvoltage, undervoltage, overcurrent, and overtemperature conditions. Fused at 25A. A 10 AWG wiring kit is recommended for installation.
80W RMS per Channel at 4Ω / 260W RMS Bridged at 4Ω: Delivers 80W RMS at 4Ω and 130W RMS at 2Ω in stereo mode, or 260W RMS bridged at 4Ω for dedicated subwoofer applications, providing flexible power output for full-range speaker and subwoofer configurations from a single amplifier.
Class D Technology - High Efficiency and Low Heat Dissipation: The Class D output stage minimises heat generation while maximising power output, making the Stage GT80021 suitable for installation in vehicles with limited mounting space and restricted airflow.
OEM Load Detect System - Factory Head Unit Compatibility: The OEM Load Detect System ensures seamless integration with factory car audio systems, preventing compatibility issues with OEM power management systems when connecting to factory head units.
Signal Sensing Remote Turn-On: The signal sensing remote turn-on function activates the amplifier automatically from the input signal, eliminating the need for a dedicated remote wire in many factory integration scenarios.
Variable Highpass and Lowpass Filters - 32-320Hz: Both the highpass and lowpass filters are independently adjustable from 32Hz to 320Hz, providing comprehensive onboard crossover control for component speaker separation and subwoofer crossover integration from the same amplifier unit.
Variable Bass Boost - 0-12dB: The variable bass boost from 0 to 12dB provides adjustable low-frequency enhancement for subwoofer and full-range bass performance tuning to suit different vehicle acoustic environments.
High-Level and Low-Level Inputs: Low-level RCA inputs (0.2-5V) accept signals from aftermarket head units and DSP processors. High-level speaker-level inputs (1-25V) accept signals from factory OEM head unit speaker outputs, providing compatibility with virtually any audio source in the automotive market. A high-level input wiring harness with Molex connector is included.
Start-Stop Vehicle Compatible: Designed for compatibility with Start-Stop engine systems, maintaining consistent audio performance and battery efficiency during momentary engine stops.
Comprehensive Protection Circuitry: Protection covers direct current, overvoltage, undervoltage, overcurrent, and overtemperature conditions, with an LED power and protection indicator for real-time status feedback.
Compact Design for Tight Installation Spaces: Compact form factor for installation in vehicles with limited mounting space including under seats and in restricted boot compartments.
| Specification | Detail |
|---|---|
| SKU | STAGEGT80021AM |
| Brand | JBL |
| Series | Stage GT |
| Generation | 2nd Generation |
| Channels | 2 (Bridgeable) |
| Amplifier Class | Class D |
| Power RMS at 4Ω (Stereo) | 2 x 80W |
| Power RMS at 2Ω (Stereo) | 2 x 130W |
| Power RMS Bridged at 4Ω | 1 x 260W |
| Total RMS Power | 260W |
| Total Peak Power | 800W |
| THD at Rated RMS | 1% |
| Minimum Impedance Stereo | 2Ω |
| Minimum Impedance Bridged | 4Ω |
| Low-Level Input Sensitivity | 0.2-5V |
| High-Level Input Sensitivity | 1-25V |
| Frequency Response | 20Hz-20,000Hz |
| Variable Highpass Filter | 32-320Hz |
| Variable Lowpass Filter | 32-320Hz |
| Bass Boost | 0-12dB |
| Preamp Outputs | No |
| Remote Bass Controller | No |
| OEM Load Detect System | Yes |
| Signal Sensing Remote Turn-On | Yes |
| Start-Stop Compatible | Yes |
| High-Level Inputs | Yes |
| LED Indicator | Power and Protection |
| Protection | DC, Overvoltage, Undervoltage, Overcurrent, Overtemperature |
| Fuse Rating | 25A |
| Recommended Wiring | 10 AWG |
| Warranty | 1 Year Manufacturer Warranty |
The Stage GT80021 is compatible with virtually any conventional audio source unit and speaker configuration in the automotive market. Low-level RCA inputs accept 0.2-5V from aftermarket head units and DSP processors. High-level inputs accept 1-25V from factory OEM head unit speaker outputs. Bridged operation requires a minimum 4Ω speaker load. Stereo operation is rated to a minimum 2Ω per channel. The OEM Load Detect System ensures compatibility with factory stereos. A 10 AWG gauge amplifier wiring kit is recommended for installation.
Can the Stage GT80021 be used to power both door speakers and a subwoofer?
The Stage GT80021 is a 2-channel amplifier. In stereo mode it powers a pair of speakers (80W RMS per channel at 4Ω). In bridged mode it drives a single subwoofer at 260W RMS into 4Ω. It cannot simultaneously power door speakers and a bridged subwoofer from the same unit - for that application, a separate amplifier for each function is required.
Does the Stage GT80021 work with factory head units?
Yes. The high-level speaker inputs (1-25V) accept direct connection to factory OEM head unit speaker outputs, and the OEM Load Detect System ensures seamless compatibility with modern factory audio systems without interfering with the vehicle power management.
What is the minimum bridged impedance for the Stage GT80021?
The Stage GT80021 has a minimum bridged impedance of 4Ω. Connecting a subwoofer below 4Ω in bridged mode is not supported and may damage the amplifier.
Does the Stage GT80021 include a bass level remote?
No. The Stage GT80021 does not include a remote bass level controller. Refer to the JBL Stage GT50011 monoblock if a wired bass remote is required.
What wiring kit is recommended for the Stage GT80021?
JBL recommends a 10 AWG gauge amplifier wiring kit for installation of the Stage GT80021.
Servicing the Illawarra and surrounding areas for over 30 years, Frankies Auto Electrics is a multi-award winning service provider and retail outlet, covering all aspects of auto electrical work and in-car entertainment. From sales and installations, electrical diagnostics and fault finding, upgrades and additions, our team of qualified sales people, technicians and installers are on hand to help.
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