Frustrated with my Mesa mark IV

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Chris6870

Chris6870

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Ive owned several Mark IVs and realized its one of my favorite amps So I bought this Mark IV for a great price, about 900 about 5 years ago. It's sounds great and is very clean. It started doing this weird thing where as soon as it warmed up, after about 5-10 minutes of playing it would lose all gainand just sound clean. I retubed it cleaned the jacks and tube sockets to no avail. I brought it to a local tech who checked basics and said he couldn't do anything with it. I bit the bullet and shipped it to Mesa at a cost of 120 bucks. Mike B went over it changed some resistors cleaned up some stuff on the board and replaced some LDRs. Mike said I could replace every LDR but would have been like 900 bucks! Or could just do whats needed. So opted for the cheaper route since * never had a problem with my other 3 MK4s I owned so figured this would be a good repair. SO i Paid another 450 for repair and return shipping. A few weeks after getting it back it started doing it again. Replaced tubes again hoping it was a bad tube but still does it.. I took it to a local authorised Mesa shop where it Sat for3 months and they never touched it because I made the mistake of telling them it was already at Mesa so he really didn't want to mess with it. So I don't know what to do with it. It sounds amazing but at this point I would probably have to sink another 8 or 900 in it by sending it back to Mesa. Ive now put it on the shelf and dialed in a nice Mark tone on on my FM3. Not sure what to do with it now. It sounds amazing for 5 minutes but then thats it, until it cools down.
 
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Sorry to hear dude, and it’s the same with techs in my area as well. I honestly get anxiety every time I turn on a tube amp, especially my older ones the inevitable snap crackle and pop is coming, and then it’s just a big problem
 
I had a Mark IVa that had some issues that sound like this maybe 8 years ago.

Took it to a local Mesa tech. They kept it for 10 weeks and couldn’t figure it out. Ended up sending it to Mesa Mike replaced some caps and sent it back. A week later, same issues occurred. I ended up sending it back and this time he offered to change all the caps. So we did that and didn’t have any more issues.

I hate to say it, but you should’ve had him do all the LDRs. $900 amp and $900 repairs is about what Mark IVs cost these days, so if you love the amp, it’s still worth it. All of them are going to start having problems. They’re getting old.

But yeah, I do not trust locals with Mesas. I had a JP I got from GC. Had some noise issues. Tech couldn’t figure it out after 45 days, so I ended up returning it to GC. And that’s not even an old amp.

Sorry for the issues you’re dealing with. Mark IVs are killer and definitely worth keeping it going. Even if you wanted to sell it you’d have to get it fixed to get what’s it’s worth.
 
sorry to hear I had a fluctuating volume issue after about 5 mins or so and it turned out to be a dirty pot. maybe one more thing to try?
 
That sucks man. Sorry to hear you have to deal with that. It is a shame you can't just have the amp you want and not have to think about dumping more money into it.

I look at tube amps like muscle cars. They sound amazing and just take more upkeep and have issues. That is why a lot of folks are just turning to other types of amps but sucks because a good tube amp can never be rellplicated.
 
Ive owned several Mark IVs and realized its one of my favorite amps So I bought this Mark IV for a great price, about 900 about 5 years ago. It's sounds great and is very clean. It started doing this weird thing where as soon as it warmed up, after about 5-10 minutes of playing it would lose all gainand just sound clean. I retubed it cleaned the jacks and tube sockets to no avail. I brought it to a local tech who checked basics and said he couldn't do anything with it. I bit the bullet and shipped it to Mesa at a cost of 120 bucks. Mike B went over it changed some resistors cleaned up some stuff on the board and replaced some LDRs. Mike said I could replace every LDR but would have been like 900 bucks! Or could just do whats needed. So opted for the cheaper route since * never had a problem with my other 3 MK4s I owned so figured this would be a good repair. SO i Paid another 450 for repair and return shipping. A few weeks after getting it back it started doing it again. Replaced tubes again hoping it was a bad tube but still does it.. I took it to a local authorised Mesa shop where it Sat for3 months and they never touched it because I made the mistake of telling them it was already at Mesa so he really didn't want to mess with it. So I don't know what to do with it. It sounds amazing but at this point I would probably have to sink another 8 or 900 in it by sending it back to Mesa. Ive now put it on the shelf and dialed in a nice Mark tone on on my FM3. Not sure what to do with it now. It sounds amazing for 5 minutes but then thats it, until it cools down.
As a prior Mesa owner all I can say is when LDR'S, SGR's, or caps start going it's best to replace them all. If an LDR, SGR, or cap goes south, then the other LDR'S are probably getting ready to join it since they're all the same age. If not your just setting yourself up to pay for the same diagnostic and repair costs a second time.
 
Crazy that Mike B sent it back with the same issue.
Yeah you have to play it a good 10 minutes sometimes longer before it happens. He probably didn't spend enough time with it. But I get it that time is money.
 
Yeah you have to play it a good 10 minutes sometimes longer before it happens. He probably didn't spend enough time with it. But I get it that time is money.
I'm sure he did a thorough diagnostic, and everything was working at the time he took readings. The man probably is the most well known and trusted tech in the entire amp industry. The difference between Mike and other techs looking at a Mesa is he has seen every single thing that can fail on them, and knows already exactly how to fix it, and knows what every measurable should read at by memory.

Like I said, usually when one LDR, SGR, or cap goes the others will follow soon. He gave you the option to preemptively replace them. You chose not too, and now the rest are going.
 
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Mesa Amps seem like a timebomb of shit to go bad. I’ve had a handful, but fortunately they aren’t the amps that are behind the sounds I gravitate to, so I’ve been moving them down the line after a short time.
 
Deeply sorry you’re experiencing such troubles with this one amp.

You had the amp in front of the likely one ideal person capable to do the job and opted for a cheaper option - which isn’t turning out to be the cheaper option after all. When someone experienced recommends something, I understand the sticker shock and money doesn’t grow on trees, but you’re back to square one having spent time and money with no change.

I’d asked him to go through it top to bottom and whatever the bill becomes is what’s necessary for that particular amp. Otherwise you’re left with no alternatives and the peace of mind is worth more than the complete repair bill because you can use the repair to maintain value at resale.
 
Mesa Amps seem like a timebomb of shit to go bad. I’ve had a handful, but fortunately they aren’t the amps that are behind the sounds I gravitate to, so I’ve been moving them down the line after a short time.
I had my Tremoverb around 27 yrs. In that time I had two SGR's go when I blew a pair of tubes in the poweramp. I had all of them replaced, as well as four new power tubes. They were going strong over 10 yrs later when I sold the amp.
 
Ship it back, ask him to replace everything he didn’t replace the first time around. Maybe he’ll give you a discount.

Either way though, remember that you’re asking him to fix a specific problem, not “change some parts.” You’re only “changing some parts” on the recommendation of someone you’re trusting to be an expert. I don’t care who it is, Mike B or not, if they don’t fix the problem you pay them to fix, then they didn’t hold up their end of the bargain. It’s not your fault they couldn’t properly diagnose the issue the first time around.
 
Ship it back, ask him to replace everything he didn’t replace the first time around. Maybe he’ll give you a discount.

Either way though, remember that you’re asking him to fix a specific problem, not “change some parts.” You’re only “changing some parts” on the recommendation of someone you’re trusting to be an expert. I don’t care who it is, Mike B or not, if they don’t fix the problem you pay them to fix, then they didn’t hold up their end of the bargain. It’s not your fault they couldn’t properly diagnose the issue the first time around.
He did fix it. OP said it worked fine a few weeks, then started acting up again. Sounds like another LDR failed, and he was offered the option to replace them all when Mesa had it in shop.
 
I have similar issue with the clean channel on my Mark IV, it has no breakup to it at all. The gain dial does nothing but increase the volume... It's all clean headroom. I know the clean channel is supposed to get a bit crunchy. Doesn't bother me too much since I just use the lead channel on this amp. I don't like Mark cleans without some kinda compressor pedal anyways.
 
Not looking forward to when my Mark IV next needs some attention. A lot of people won’t touch them and only a fraction of those that would am I likely to trust!
 
I know it's my fault. I took the gamble and lost. Not blaming Mike at all.
I'm liking the Fractal Triaxis model so will probably just shelve the amp and use the Fractal for that. I am lucky to still have some other tube amps.
 
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I would send it back and have Mesa go over it again since they already fixed your amp once. They may give you a break in the price of the second repair since you are still having issues with the amp after they went through it (could be a completely separate part that failed from the first time, but who knows). If they don't, the reality is that all tube amps need maintenance and repairs at some point, and that's part of the cost of ownership. Kinda like a car.
 
Stories like this make me wish I still had a SS rig. Never really had issues with most of the Randall's and Ampeg's I've owned, and they still delivered a brutal as fuck tone. Maybe not as warm sounding but who needs warmth??
 
I had my Tremoverb around 27 yrs. In that time I had two SGR's go when I blew a pair of tubes in the poweramp. I had all of them replaced, as well as four new power tubes. They were going strong over 10 yrs later when I sold the amp.
That’s great! I don’t mean to necessarily imply that they are unreliable, rather that should something happen, there is generally so much going on in a Mesa that troubleshooting can be daunting.
 
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