POWER AMP experts!!!

[11miles]

My mesa 50/50 nailed me in the middle of a gig!

A week ago or so, i expirienced a bad tube syndrome. One of the 4 did not glow as the other three, but considerably more.
Anyways, the sound was not as good, but did not have the dough to change it!

The question was can i change just 1 tube, instead f all 4? I mean the other 3 works like a charm!

Anyway i did not change anything and not put even a finger next to it and took my rig for a ''little ride in the park'' (gig) and in the middle of the concert my fuse blew and the mesa saga was over?

What the hell is wrong?
Just tubes or something a lot more?

Change the tube/tall tubes and offcourse the fuse. Or go to a tech and have a look-see?

[Cleveland Metal]

Re: POWER AMP experts!!!

Obviously you don't want to hear this. But, I would replace all four power amp tubes.

Since there is no potentiemeter for biasing, MESA amps can be retubed without getting them biased "IF" using tubes matched to the same color coding that they provide.

Whether you you use their expensive MESA logo crap tubes, or contact the tubestore.com or lord valve etc, and get their higher quality and equivilantly matched tubes for your color code is your choice. I'd choose the latter and buy Svetlanas from the tubestore.

The flip of the coin is whether to install them and take the chance that your amp isn't hurt, or to have a tech look the amp over prior to installing them.

If the tube took out some associated parts when it left, then there is a chance you "may" damage the new tubes if you just throw them in.

It may just not work, or it may hurt the tube. I'm thinking it would likely just not work if other stuff was hurt. But, I'm handing you the warning that it could damage the new tubes, as I'm sure it could be very possible.

Personally, I'd have it apart examining for obviously burnt parts first myself, and would recommend a non techie to have it looked over by a tech.

Of course,the tube may have just poofed and popped a fuse and all is otherwise well. Having a tech look it over isn't a bad idea at all. Probably not expensive and definitely safe advise.

If you stick your hands in the amp to retube, be very careful about touching things, there are extremely lethal voltages inside long (weeks)after the amp has been off. Keep one hand behind your back or away from the amp as a shock across the chest is more dangerous than say a shock to one hand.

[11miles]

Re: POWER AMP experts!!!

Cleve you are right, i did not want to hear this!
But...

I was wondering, if 1 tube is bad and the other 3 all good, glowing very nice and as they shoul, what should i do with them?
Throw them away?

Is it impossible to find a tube with the same value as the 4 that are in stock?

I just dont get it!

I aprecciate it tough, telling me about the hand behind my back!
Willl do!

I wont even touch it and take it to a tech to have a look see!
Other wise i thought of shipping it to Mesa but being from Europe that is nto very wise idea.
Although it is still in warranty. The mesa/ tubes are short of 1 year old! Burt i play 3 times a week, which certainly qualifies as a lot, dont you think?

[MSGfan]

Re: POWER AMP experts!!!

Try ordering one tube of the same style and color code from Mesa if you can't afford a whole new set. I ordered one 6L6 over the phone and charged it and received it on the east coast in a week! Hey, it's worth the effort and could save you some cash like I did instead of spending the over $100. it would have cost me if I retubed my whole Triple Recto Head. Good luck!

[11miles]

Re: POWER AMP experts!!!

Outlander, yes i did get your mail and did help me!
At the time i am not running 2 pre's at athe same time bt am very much interested in!
I once tried but the feedback was just too much!
Thanks for the advice, when the right moment comes along i will most definitely try it out!

But for now i have a different poroblem!
My mesa is in a coma!

What do you think went wrong if first a tube lost its original glow and in a weeks time the fuse blew?

What could be wrong with my baby?

[Soloist1]

Re: POWER AMP experts!!!

Could be any number of things. It could simply be the bad tube that is causing it. Also I wouldn't recommend buying one tube and just throwing it in there. It will work but your other tube will die quicker if it does.

My suggestion for you is to sell your 50/50 and buy a solid state amp. Tube amps sound great but if you don't have the cash to change tubes properly, meaning all at once, then you should consider an alternative that costs less. I hear some of the Roctron Velocity power amps sound fairly close to a tube power amps as well.

But if you aren't comfortable going inside the amp to see if something burned up and/or don't plan on changing all the tubes at once and/or go to a tech to have it done, I'd say tube power amps aren't for you.

[11miles]

Re: POWER AMP experts!!!

Thanks for the advice!

But you dont seem to get me?
I just think its a shame to throw away 3 perfectly good tubes just because one is not glowing anymore!
I will let a tech look at it and fix the problem! No problem, changing tubes at once is not a problem eihter!

But a waste of 3 other tubes?

Anyway, soldstate amps? [img]graemlins/laugh.gif[/img]

[Cleveland Metal]

Re: POWER AMP experts!!!

They're not perfectly good tubes... They are used tubes and one of them has already failed... The others could somewhat soon to follow.

Replace the whole set at one time. That's why they sell matched pairs/quartets etc. I've probably spent thousands of dollars on tubes in the last 25 years I've owned tube amps. You want the tone, you have to pay.

[Outlander]

Re: POWER AMP experts!!!

11miles I believe the Mesa manual recomends replacing the power tubes at least once a year with average usage of 3 to 4 nights a week. More often like every 6 months or so if you use your amp more than that,don't forget rehearsal time and fooling around time counts too!
They say you can hear a difference of tone and power as they wear down. Did you notice any of this?
I bought their 20/20 because it's cheaper to retube (much cheaper)and I love the EL84 tone,they saturate fairly quickly and also it's much lighter to handle.
You should have a five year warranty see if there is a authorized service source in your area or call Mesa's tech help line and let them advise. I know it's a major pain having to use something else if you have to send it in.Out here in Arizona one of the local Guitar Centers and another store will actually loan me gear while mine is repaired especially if it's fairly new gear and I bought it from them.
Good Luck hope every thing works out..charlie

[Outlander]

Re: POWER AMP experts!!!

Matjaz did you ever get my e-mail? I'm curious because of your location and distance.Are you running two pre amps now? ....charlie

[11miles]

Re: POWER AMP experts!!!

Again...

I really do not mind paying 80$ for retubing my baby especially when i know how good it is going to sound!
Once a year, no problem?

I will do it and ask no more.

Does anyone have a cue what caused the fuse to blow? Something serious?
If a tech that looks into my baby messaures everything and nothing is wrong, no bad circuit, nothing broken, etc.
Should i just retube and of we go playing?

What else should i do right?
By the way i get my Tc today or tommorow, can't wait!

How about it cleve?

Spent myself around 220$