Mesa Lonestar Special 1x12 5w Setting Dead Failure

Hi, I have a problem and hoped someone could help.

I was testing the Solo switch which I don't use often and found it was behaving in an unusual fashion...eg on the clean channel, the Solo was way louder than "non Solo" even when the Solo knob turned right down....the drive channel was strange too.

The main thing though was that the 5W setting on either the Clean or Drive channels is NOT WORKING.

The 15W and 30 W are working.

I have since gone back to the Solo knob / switch positions and it now seems to be working more like normal...but I'm not sure.

The main thing is that the 5W settings on either channel are Dead and I believe this is unusual.

Sorry if the references to the Solo position are confusing but I am somewhat confused.

It would be brilliant if someone recognises this issue.

Thanks.

Richard

I would try the changing the rectifier tube. Usually when the 5 watt setting dies, this is the issue.

Hi, Thanks for the response.

I'm willing to buy a new Rectifier tube but hesitate because I thought both the 5W and 15W positions would go dead if the valve/tube rectifier had failed?

Is it possible for the 5W to stop working yet the 15W continue to work due to a bad Rectifier Tube?


In my case only the 5W setting is dead.

Thanks.

Richard

I would try swapping round the 4 output tubes, as the 5w mode uses only 1 tube. No idea why the solo function would play up, but it won't cost anything to try swapping the tubes round.

Thanks for that.

I had been talking to Orestie at Westside Distribution (UK MESA Distributor in Glasgow) and he agreed that if the Rectifier had gone both 5W and 15W settings would fail together.

He identified that the two outer tubes serve the 15W setting and the one closest to the Reverb in/out sockets were for the 5W single tube setting. He suggested I try swapping this one for one of the inner power tubes. I did this and it didn't work (He wasn't certain but thought it was worth trying).

I then had your reply about swapping the power tubes in general so I had another go.

This time I swapped the one beside the rectifier for the inner one next to it and....the 5W channel came back on again.

Given that Orestie looked up the manual and said the outer power tube beside the reverb connectors was the one serving the 5W setting, I have no idea why the one at the far end (or it's neighbour) has solved the problem.

If anyone understands what is happening and was willing to share your thoughts, i would find it very helpful.

I have ordered a new set of 4 Mesa EL84 valves and hope this solves it properly.

In the meantime, THom, thanks very much for your suggestion.

Richard

PS After the solo switch playing up, I discovered the 5W setting wasn't working. As I investigated, I found the footswitch which operated the channel switching and solo was also misbehaving.

I opened up the stereo jack into the footswitch and found a bad connection which I re soldered.

The Solo function is now working normally as is the Footswitching.

While I have the 5W, 15W and 30W settings functioning, I suspect a dodgey power valve so I'm not certain the combo is totally sounding OK but I'm hoping a new set of power valves will put it right

Glad you got it working again. Re the power tubes, I just had a look at the manual and under the section describing the function of the power selector switch it states that the tube to the "far left facing rear", is the one that is used for the 5W mode. That would be the one near the rectifier valve so I guess the guy at Westside was mistaken.

Hi Thom,

That that does make sense and I find it very encouraging.

I have 4 new Mesa EL84's on the way from Hot Rox UK so if all goes well I'll be fixed.

By the way Hot Rox were very good to deal with.

Thanks Thom.

Richard

Cool. I have used a company called Voc Rock fairly recently; rang them up and the guy was very knowledgeable; just make sure you tell him the valves are for a Mesa so they can send out some suitable ones. Got them very quickly and its always great to talk to someone who knows their stuff. I use JJs for the power tubes btw, but not that keen on JJs for the preamp tubes.

Yes, I saw that company's presence.
I suspect Vox Rox were better value on this occasion.
For JJ's I have used www.eurotubes.com in the USA....Bob Pletka.

Because I was dealing with a repair type problem I decided to stick with the MESA valves as they recommend them strongly for the power tubes...You know, pre selected for this fixed bias amp.

Otherwise, I'd have been more open to go for the JJ's.

Eurotubes are very certain they can put suitable JJ sets together.

I had that problem too. My Mesa Boogie Lonestar Special was only a few months old. I noticed that it did not give me the effortless feedback I was used to (I play with high gain). Then one day the slo blow fuse went. I replaced it but it sounded crap. I then noticed that there were problems between the wattage settings. I replaced the rectifier but when I matched it to the book settings (which previously sounded great) it was crap. I ended up having to replace some power thing which cost £65 from Glasgow place.

Now only after 7 gigs it's gone again. Loss of volume and now today it just don't work. Still less than a year old. Shop I bought it from has closed. I'll never by Boogie again. I may have a dog of an amp but I'm stuck with it now. Why oh why O I flogged my Fender Twin to get this I don't know.

Hi Jason,
sorry to hear about your problems. The sickest feeling in the Music world for me.
I did get good conversational support from the UK Distributors in Glasgow, Westside Distribution. there's a guy there called Orestie...very decent. They do supply valves etc but have strict pricing which means they may not be best priced...I did better for valves elsewhere (see above).
They do have a repair guy who I believe is fair. I previously had a problem (Bad Standby Switch Interrmittent Cut out) and they fixed it. I took out the amp chassis and sent that which they fixed and returned..

All the best,
Richard

Cheers Richard. I spoke with Orestie and I'm sending it to them today. I took the amp out from the chasis and boxed it. I hope they find the problem and fix it under the warranty. I think when it gets fixed I'm going to get rid of it. I had Marshall half stack and fender twin before and they never let me down, this one has been tough. It does sound good but has failed and under performed for most of the time I've had it. Cheers.

Just spoke with Oreste. We have put things together and worked out that the shop probably sold me a second hand one and lied that it was new. The shop was not a dealer and I remember having to replace a valve straight off. Anyway I've sent it off now and I'm sure they will get to the bottom of it. I think I'll lay off moaning about Mesa until I've got to the bottom of it at least. The amp was gorgeous when it worked just makes it more disappointing when it goes wrong.

Hi Jason,
I'm glad things are moving forward.
You feel better when positive action has been taken and you know its being looked at.
On my last problem, I felt likeselling fine too. Makes you feel very insecure.

In fact, my last issue was a simple case of needing apower valve replaced which of course is not unreasonable.
Once we figured it out and did it, the amp's running great now.

....and I'm not thinking of selling,Ha!
Richard