Amp stopped working blew fuse need guidance

I have an Emerald Physics amp that recently stopped working. I figured it probably blew the fuse so I opened it up. Not sure if the fuse was blown or not as when I was trying to remove it it shattered. It looked black and cloudy inside the glass so I assume it was blown. Upon further inspection I noticed that the insulation on the two positive wires coming from the binding posts was browned and slightly melted. I am wondering whether or not to put a new fuse in or to send it in for service. It is still under warranty. I am just afraid that something may be fried and would not want to put an expensive fuse in and have it blow. The wires are not melted bad but are browned and had a few brown bubbles rising from the insulation. What would you guys do? Thanks for any help.

Get it checked out. Replacing a fuse without any idea what caused it to fail is asking for trouble!

Please explain further. Are the affected wires coming from the speaker binding posts to the current amplifier transistors? If so, you may have had a short in the speaker which led to high current, thus the blown fuse. Try replacing the fuse with a cheapo fuse of the same type (size, current rating, fast or slow blow) and see if it still works. If it blows immediately, there’s a fault. Then you have to determine if the speakers are shorted (< 4 ohms) or if the amp is doing something funky.

A picture would be helpful.

Best of luck!

–SSW

“black, cloudy, browned, slightly melted…” Unplug it and send it back.

Here are a few pix, not sure if you can tell much as my phone is not the best.


I don’t think it is the speakers as I have hooked up another amp to them and had no trouble. Would I be able to buy a fuse locally? I am talking about an el cheapo just to see if it blows. Any national chains that would carry fuses like this? small 5a fast blo

The wires look the way they do from them soldering them to the terminals. An auto supply store has glass type fuses be sure it is the same rating and type fast blo etc.

ok thanks guys for all your help much appreciated.

So what did you decide to do?

I ordered some cheap ceramic fuses off amazon and will use one of those. If it blows I will send it in for service if it doesn’t then I guess I am ok.

Sounds like a good plan.

I wouldn’t deviate from the original fuse specs. And I suspect that you will eventually find out what originally blew the first fuse.

Thanks Ron, I ordered the exact same spec fuses. I am thinking that a power cord that is now out of my system may be to blame. It had an abnormally long ground plug that made it difficult to insert fully. I have been using another amp with no problems so far.

Good to hear. And always be sure that the power switch is off before you unplug or plug in anything. I’ve made that mistake and blown fuses every time.

UPDATE: I received some ceramic fuses and inserted one and the amp is fine. Thanks guys for all your input was a little worried about firing it up again but you guys talked me through. Many thanks one of the reasons I keep coming back to this site. Friendly, knowledgeable folks who are willing to help.

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