Bassman blowing fuses all of a sudden

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macula56
Posts: 27
Joined: Fri Jan 14, 2005 7:14 pm

Bassman blowing fuses all of a sudden

Post by macula56 »

My Bassman started blowing fuses for some reason yesterday. I played it with no problems Monday and Tuesday and yesterday it started blowing fuses. I was banging out some power chords and it just dies. I replaced the fuse and went back to the power cords and it died again. I replaced the fuse again and tried just playing some nice quiet stuff and it was fine until I stated bashing out some power chords. I've never had an amp do this so I was wondering where to start looking for problems. I checked my bias voltages and everything looks normal. Tubes are biased around 35 ma like usual. Tubes are not wobbling around. Nothing has changed physically that I can see. I did a search about fuses blowing but didn't see anything that sounded like my particular issue. Anyone ever had this happen? As always, any help greatly appreciated. Thanks, Jmac.
Chris G
Posts: 300
Joined: Mon Jan 17, 2005 5:27 pm
Location: rochester n.y.

Re: Bassman blowing fuses all of a sudden

Post by Chris G »

Bad power tube.. does it have a tube rectifier? drawing to much current...
macula56
Posts: 27
Joined: Fri Jan 14, 2005 7:14 pm

Re: Bassman blowing fuses all of a sudden

Post by macula56 »

diode rectifier. tubes are fine. i put them in another amp and they work great.
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Phil_S
Posts: 6048
Joined: Tue Oct 23, 2007 10:12 pm
Location: Baltimore, MD

Re: Bassman blowing fuses all of a sudden

Post by Phil_S »

All rectifiers are diodes :D I think you mean it's solid state!

I believe what Chris is getting at is that when you drive the amp hard (power chords) the power tubes are drawing excessive current. These tubes may work fine in another amp and I'm not sure that tells us much. It would be better to try different tubes in the amp that's blowing fuses.

Maybe you are simply overdue for a cap job. Try a tube swap first.
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