Word Count: ~1,200 words Target Audience: Electronics hobbyists, audio engineers, car audio installers, and repair technicians. Introduction The NX Audio RX 4000 is a legendary contender in the world of high-power car audio amplifiers. Known for its aggressive styling, robust build quality, and surprisingly clean power output, this Class AB amplifier has been a favorite for driving subwoofers and high-end component speakers for over a decade.
While the RX 4000 is a brute-force amplifier—relying on massive transformers and robust transistors—it is surprisingly repairable if you understand its signal flow. Download the schematic, buy a pack of IRFZ44Ns and 2SC5200s, and bring this club thumper back to life. nx audio rx 4000 circuit diagram
| | What it looks like on the real RX 4000 PCB | | :--- | :--- | | Ground Symbol | Large copper pour, usually around the mounting holes and RCA shields. | | Vcc (+15V) | Thin red trace or a bus wire running to the preamp section (8-pin ICs). | | Output Transistors | Large TO-247 or TO-264 packages screwed to the center heatsink. | | Zobel Network | A 10 Ohm resistor and a 100nF capacitor connected directly to the speaker output terminal. (Stops oscillation). | While the RX 4000 is a brute-force amplifier—relying
Always discharge the main filter capacitors (those two large 4700uF or 10,000uF cylinders) before sticking your probe in. The RX 4000 stores enough voltage to bite back—even when unplugged. Do you have a burnt resistor in your RX 4000 and can't read the color code? Leave the component number (e.g., R117 or D203) in the comments below, and we will cross-reference it with the master schematic database. | | Vcc (+15V) | Thin red trace