Just so, why does my amp have power but no sound?
This is a sign that the amp is being overtaxed by a subwoofer or other speakers to the point where it simply can't provide enough power. If you find that the amp has plenty of power for the application, then there could be a problem with your speaker wires, the speakers themselves, or the amplifier's ground.
Likewise, how do you troubleshoot a guitar amp? Try a new rectifier tube. Try plugging in a guitar cable, turn up all the amp's volume, gain and master volume controls up a little and touch the tip of the guitar cable's other end. You should hear loud noise. If you hear noise jump to The amp shows signs of life but does not put out any guitar audio.
Also asked, why is my sub not working?
Starting from the subwoofer, check all the wires and connection points running to amplifiers, receivers, or speakers. Check to make sure that cables are firmly connected and plugged into the correct spots. Check outlets, power cable, and fuse. Most subwoofers have a "standby" LED that glows to indicate active power.
How do I know if my amp fuse is blown?
Usually a fuse blows due to a failure in the amp, but occasionally it's due to something as simple as a power surge. Because fuses can sometimes look good to the naked eye even when they're blown, the best way to check is to use a multimeter. Set the meter to read continuity in ohms (Ω) and measure across the fuse.
