JBL Stage A9004 (D class) power amplifier (4-channel).

JBL Stage A9004 (D class) power amplifier (4-channel). 

Affordable performance
Now you can get JBL sound quality with an entry-level price tag. Their Stage A9004 4-channel amplifier sends 90 watts RMS to each of your front and rear speakers, adding impact and clarity to your music. 
You can also use this versatile amp use in 3-channel mode to power a pair of speakers up front while sending up to 140 watts to your sub.

Works in almost any vehicle
Speaker-level inputs allow this amplifier to work with most systems, even if you're keeping your factory radio. Separate high- and low-pass filters maximize your system's performance. 
The front and rear channels also feature a bass boost so you can make your subwoofers sound their best.

Value Engineered.
Stage amplification provides true JBL performance at an affordable price while now lacking the features needed to properly tune and optimize performance.

Compact Footprint.
With it becoming more and more difficult to find spacious locations for amplifier mounting, Stage has been developed in a small compact form factor to allow more location versatility.

Full On-Board Protection.
Stage amplification has on-board circuitry to protect them from shorts, temperature, overvoltage and undervoltage. An LED indicator is included on all four models to let you know when one of these condutions exists.

Input Level Control.
When Low-level inputs are used, this control adjusts the input sensitivity between 200mVrms and 5.0Vrms. When High-level inputs are used, this control adjusts the input sensitivity between 0.5Vrms and 15Vrms.

Reliability.
JBL is one of the greatest audio brands in the world. This is not a coincidence given the arduous testing and quality control. We take our craft seriously and want every consumer to have a world class experience that lasts and lasts.