Why does my amp keep blowing fuses when I turn it up?

In most cases, an amplifier will blow fuses due to internal damage caused by the way it was installed. An amplifier that blows the main power fuse immediately after you turn it on or when the fuse is inserted into the fuse holder is usually damaged in its power supply or output section, and will require serviced.

Do amplifiers have internal fuses?

Types of Fuses for Amps Most amplifiers that have internal fuses use some type of automotive fuse. These are the same type of fuses that are used elsewhere in your car, and other audio components, like your head unit, may also use very similar fuses.

How do I know if my amp fuze is blown?

In some cases you may need a small screwdriver to unscrew the fuse holder cap. Look at the fuse wire. If there is a visible gap in the wire or a dark or metallic smear inside the glass then the fuse is blown and needs to be replaced.

What happens when a fuse blows on an amplifier?

The fuse is in the amplifier to protect the amplifier’s circuit from tube failure and other extreme voltage issues! When the fuse blows, its not the fuse that’s actually bad. Obviously a blown fuse will no longer allow the amp to function… and that’s by design.

What do you do when your fuse blows?

Also helpful in a blown fuse situiation is an indication of when the power or rectifier tubes were last changed in the amp. Make a note of what tubes were changed and when and write this info on a piece of tape or a label-maker and attach somewhere on the amp as the finishing touch to the retube job.

Can a power surge cause a fuse to blow?

This is generally rare, BUT… trying more than 2 fuses without addressing your power or rectifier tubes can cause further damage to the amp. OK… you know that preamp tubes aren’t the cause of a blown fuse and you’re pretty sure it wasn’t a power surge so you’re ready to move on to the next steps.

Can a preamp tube cause a fuse to blow?

Whole sets of tubes do not fail. – Preamp tubes will not cause a fuse to blow. (whew… check that off the list!) Preamp tubes are not high voltage like power or rectifier tubes and will not cause a fuse to blow. – Feeding multiple fuses to an amp is not fixing it.

Why are the fuses not blowing on my amplifier?

If the battery fuse blows ‘as soon as it’s inserted into the fuse holder’ (amplifiers off), the problem could be anywhere in the power distribution line. If the system is set up as shown below, and the fuses in the dblock are not blowing, the problem is likely a direct short to ground between the main fuse block and the dblock.

What should I do if my amp blew a fuse?

“Lightning” (arcing) or amp shutdown (blown fuse) at this stage indicates a bad Rectifier Tube. If the Rectifier Tubes are OK, move on to testing the Power Tubes. Start with the POWER and STANDBY switches down (Off). Load in one Power Tube (any) ** (See Note 2 below).

When to replace a fuse in an amp?

When an amp blows a fuse (or fuses, for amps with multiple fuses), you should replace the blown fuse with a fuse rated for less current. Let’s take an amp that has two 30 amp fuses. If the OEM recommended fuses blow, there is likely a serious problem.

What happens to the voltage when a fuse is blown?

When dark, there is no voltage on that point in the circuit. When a fuse is blown, there is voltage on only one side of it. When the fuse isn’t blown, the voltage is the same on both terminals of the fuse. In the image below, you can see that there is voltage on every point.