Bad bad news!

[Gibson07]

So last night i was late to band practice and in my haste to set up I accidentally plugged the speaker lead into the slave and not the correct position. This meant that when I switched the amp on there was no load to the cab (3ch dual recto into 4x2 cab btw).

A fuse blew but an it also damaged the amp (as indicated by a bad burnt smell and the fact that the amp just makes an awful buzz when turned on). I won’t be able to take it to the amp doctor until next week to get the bad news but in the meantime does anyone know the probable extent of the damage? Is it fix able? How much do you think it will cost?

Also; I know how stupid I am for not checking the cable (trust me I am shattered by the event) so you don’t need to remind me of this. I have been meaning to put tape over this jack ever since I got the amp to prevent it also.

Thanks

 

[Addictedtokaos]

Thats why it is nice that Mesa includes a fuse. Being new to tube amps myself, Ive blown my fair share of fuses. All resulted in blow power tubes.

Check your power tubes and replace the pairs that are fried. Replace fuse. Make sure speaker cable is plugged in properly and fire it up.

 

[Jorn218]

A fuse blew but an it also damaged the amp (as indicated by a bad burnt smell and the fact that the amp just makes an awful buzz when turned on). I won’t be able to take it to the amp doctor until next week to get the bad news but in the meantime does anyone know the probable extent of the damage? Is it fix able? How much do you think it will cost?
Thanks

From my experience with tube amps and accidents like what you experienced. Best case scenario, blown power tubes and screen/grid resistors. Worse case scenario, blown power tubes, screen/grid resistors, shorted out tube sockets, burnt board traces, blown power transformer, shorted out components adjacent to above. In other words, either you just crapped out your powertubes, and the resistors connected to the tube sockets and maybe one to all of the sockets, OR.........., you took everything out between the power cable socket, and the power tubes.

Not trying to scare you. My best advice is the hope for the best, prepare for the worst.

Cost wise, prepare for a new set of power tubes, and phase inverter tube, possible rectifier tubes, up to $20 in resistors, capacitors, and 2-3 hours max bench fee(first hour being troubleshooting and putting amp on bench)at the very least. Worst case cost, includes a power transformer and another $10-15 in component parts.

I've smoked a few tube amps myself. Nothing scares a guitarist's wallet more than flipping standby off and seeing smoke and smelling that tell tale burnt bacon smell of the power tranny going. Well, "I'm pregnant"!, comes a close second.. :lol:

I am sure its just in need of some new resistors and a new set of power tubes. My suggestion is make sure all the power tubes plus phase inverter tube gets replaced. They probably all don't need it, but they all took a slapback voltage hit. Best to be safe then sorry.

 

[domct203]

......... Also; I know how stupid I am for not checking the cable (trust me I am shattered by the event) so you don’t need to remind me of this. I have been meaning to put tape over this jack ever since I got the amp to prevent it also.

Thanks

Don't use tape, these work awesome.

http://www.ebay.com/itm/100-1-4-BLA...Parts_Accessories&hash=item45ff277753&vxp=mtr

I put them in every unused jack on my amps & PA gear. Not only does it keep you from plugging into the wrong jack, it keeps the dust out. Plus when you remove one there is no sticky residue, and they can be reused.

Dom

 

[knotts]

Thanks Dom. There are about 100 jacks open on my roadster that are open so I will need most of the pack. I keep a dust cover on it, but these will surely provide an additional layer of protection...

 

[Gibson07]

Thanks for the information guys, I hope it is just the power tubes. I will order some new ones next pay day and get it to a tech for a look over. I do have some spare tubes also an plan to change them over as a test when I get a chance.

I will update this post with the results for peoples information in the future.

Dom – I will definitely get some of those plugs! A few dollars could save many dollars when hastily setting up on dark stages etc.

 

[Gibson07]

So I just want to provide an update so people can search the forum if they suffer a similar problem and get some information.

I changed all the power tubes and rectifiers over and the amp powered up and worked fine!! So happy!! I have not had the time to trouble shoot the old tubes to find if one or more were damaged but will do out of interest. Thanks for the responses!

 

[knotts]

Glad to hear that you're back up and running with little damage. I bet you won't be doing that again anytime soon.

 

[screamingdaisy]

I'd toss the old tubes. Not worth the risk of damaging anything just to satisfy curiosity.

 

[Elpelotero]

Yes, it's best to toss them out. Otherwise you'll go through quite a few fuses trying to figure out which is the bad one.

 

[elvis]

Don't use tape, these work awesome.

http://www.ebay.com/itm/100-1-4-BLA...Parts_Accessories&hash=item45ff277753&vxp=mtr

I put them in every unused jack on my amps & PA gear. Not only does it keep you from plugging into the wrong jack, it keeps the dust out. Plus when you remove one there is no sticky residue, and they can be reused.

Dom

Dom, I bought some of these and they work great. Thanks for the tip!!

 

[domct203]

NP Bro, glad I could help!

Dom

 

[Gibson07]

Thanks guys, the old tubes are in the bin on your advice and a whole new set in and the amp is working fine. I will certainly take more care and have ordered some plugs to make sure it doesn't happen again.