New Mark IV crackling . . . low volume. Power tube, right?

[LEVEL4]

I have a "new" Mark IV rackmount (was in a Lucite display case for a couple years at the Mesa store) that started crackling a few days ago. Volume dropped in and out as well. I just re-seated all the tubes, and the problem still persists. In the past 48 hours, now, I've got nothing but crackling, and ultra-low volume. I'm assuming the problem is power-tube related? Guess one should ALWAYS have a replacement tube of each type to troubleshoot.

Anyway, since I bought it directly from Mesa's outlet store, I got a five-year warranty with it. Gonna have them check it out tomorrow.

 

[LEVEL4]

Well, let me just say that the tech at the Mesa/Boogie Hollywood store, ROCKS! We plugged in my Mark IV, and, guess what . . . NO PROBLEM. Of course, the amp sounded just fine, the minute we plugged it into a cabinet. By the way, Mark IVs sure do sound awesome through a Mesa V30-filled 4x12.

But, thank god, it finally did f*ck up before I gave up and left. The tech stopped playing for a minute, and then the crackling started, THANK GOD. It took the tech only about five minutes to put it on the bench, and diagnose the problem.

As we found out, all the tubes were fine. It was a leaking capacitor that had shorted out some of the traces on what he called a "sensitive part of the board." He cleaned up the PCB, and resoldered a new capacitor in place. He also replaced my "iffy" red EQ LED. But, he was out of red LEDs, so he put a yellow one in (they don't have little blue ones). Okay, so now my Mark IV is "special." All performed under warranty repair, free of charge. I walked out of the store after waiting about 90 minutes, with my amp totally fixed!

Thank you, Mesa/Boogie Hollywood!

 

[trem]

Congrats man. I know how that feels!

 

[MesaDCLP]

Doing the repair on the spot ... Now that's excellent service!!!

 

[LEVEL4]

Yes! EXCELLENT service! Huge kudos to Mesa/Boogie Hollywood!

BUT, there's always SOMETHING, though, isn't there? So I just got home, all excited to try out my new Voodoo Labs Amp Selector I got from the Mesa store today. Mesa/Boogie was the ONLY place that had it in stock. I mean, like, NO ONE has it, not even online! Anyway, so I excitedly plug in my newly repaired Mark IV and . . . no sound? I'm like WTF??? I try different cables, everything. THEN, I realize I forgot to plug in the speaker cable to the amp!!! DUH! After a mild heart attack, I find the speaker cable coiled on the bottom of the rack and plug it it. Turned it on, and everything seemed okay. Whew! Okay, we're rockin' NOW!

So, I plug in my Mark IV, DC-3, and my Single-Recto into the Voodoo switch, and . . . WTF??? No Recto! I check all the cables like 300 times. Then I plug in direct into the Recto, thinking there's something wrong with the amp selector switch . . . NOTHING. Guess it's back to the Mesa repair shop for the Recto now! Hopefully, it's only a tube this time. Because, it's a used Recto, all the repair work will be on my dime.

 

[shredding]

Yes! EXCELLENT service! Huge kudos to Mesa/Boogie Hollywood!

BUT, there's always SOMETHING, though, isn't there? So I just got home, all excited to try out my new Voodoo Labs Amp Selector I got from the Mesa store today. Mesa/Boogie was the ONLY place that had it in stock. I mean, like, NO ONE has it, not even online! Anyway, so I excitedly plug in my newly repaired Mark IV and . . . no sound? I'm like WTF??? I try different cables, everything. THEN, I realize I forgot to plug in the speaker cable to the amp!!! DUH! After a mild heart attack, I find the speaker cable coiled on the bottom of the rack and plug it it. Turned it on, and everything seemed okay. Whew! Okay, we're rockin' NOW!

So, I plug in my Mark IV, DC-3, and my Single-Recto into the Voodoo switch, and . . . WTF??? No Recto! I check all the cables like 300 times. Then I plug in direct into the Recto, thinking there's something wrong with the amp selector switch . . . NOTHING. Guess it's back to the Mesa repair shop for the Recto now! Hopefully, it's only a tube this time. Because, it's a used Recto, all the repair work will be on my dime.

LOL. Sorry about your recto. Glad you enjoyed your Mark IV. I didn't plug in the speaker cables for a few times and that's in fact really bad for the output transformer as I heard. I always check the speaker cables first before powering on the amps.

 

[LEVEL4]

Thanks! Well, I just put two Ruby 6L6 power tubes from my 6505 (I pulled these a while back to drop my 6505 to 60 Watts) into my Recto. I re-seated all of its preamp tubes too (they all looked fine, visually, anyway). I'm guessing the 6505's Ruby 6L6s are close enough in bias to the JJs that were in the Recto already. My Recto sounds fine now, and has been playing okay for over an hour now. Got all four amps (Mark IV, DC-3, Recto, 6505) into the Voodoo A/B/C/D switch now, each amp into its own cabinet. Suh-weeeet!

 

[shredding]

Thanks! Well, I just put two Ruby 6L6 power tubes from my 6505 (I pulled these a while back to drop my 6505 to 60 Watts) into my Recto. I re-seated all of its preamp tubes too (they all looked fine, visually, anyway). I'm guessing the 6505's Ruby 6L6s are close enough in bias to the JJs that were in the Recto already. My Recto sounds fine now, and has been playing okay for over an hour now. Got all four amps (Mark IV, DC-3, Recto, 6505) into the Voodoo A/B/C/D switch now, each amp into its own cabinet. Suh-weeeet!

Sweet! Now you are have rig bigger and has more tone variety than Petrucci's! Just that is simply an achievement!

My first mesa amp was a DC-3 which I ended up trading for a Dual rectifier b/c I can't get enough bass out of the EL84's and its smaller tranny. Then I traded my DR for a TR and then traded that for a mark IV. Gigged with my mark IV for 7-8 months and I can't be happier. You will probably one day trade that recto away.