Hi, board newbie here. Just wanted to share my recent experience -- I bought an Express 5:25+ combo about 6 months ago - I love the amp but I occasionally noticed a slight static noise. The noise would periodically get worse, but only when I played loudly (which I rarely do - I mostly just practice at home but occasionally bring it to a jam session with another guitarist and a drummer.) It got to the point where it happens consistently on the 6th string 5th fret and lower.
Long story short, I tried swapping tubes, no joy - I called MB and they referred me to the local authorized repair guy who has a 3 week wait, you call and get on his list and he calls you when he's ready for you to drop off your amp. While I waited I started looking for burn marks on caps, resistors, transformers and solder joints at the wires soldered onto each pot and there I see it: The third wire going to *both* Reverb pots was resting in the little hole on the pot pin but wasn't soldered - if you remove the head from the combo chassis it's the right most wire if you're looking at the board from the back.
I called Mesa to see if this was normal since it seemed odd that the assembly tech would miss the same wire on two pots. They checked and confirmed that of course all three wires should be soldered down. I get "permission" from the Mesa tech to solder the wire without violating my warranty, 3 minutes and a little bit of rosin core solder and the static was gone -- turns out the vibration from the bass notes was shaking the circuit board just enough to cause those two wires to lose contact with the pots!
I'm not grinding on Mesa - I love the amp and love that it was actually hand built in the USA. I traded in a Marshall DSL15C for the 5:25+ and it was one of the best decisions I've made - I love this amp at bedroom practice levels on the 5W setting on both channels (even late at night when the kids are asleep), and it get's plenty loud with great tone to keep up with a drummer at the 15W setting, and at the 25W setting it's louder than I would need for any venue I'll get invited to play at. Super convenient weight too.
Rock on!
Long story short, I tried swapping tubes, no joy - I called MB and they referred me to the local authorized repair guy who has a 3 week wait, you call and get on his list and he calls you when he's ready for you to drop off your amp. While I waited I started looking for burn marks on caps, resistors, transformers and solder joints at the wires soldered onto each pot and there I see it: The third wire going to *both* Reverb pots was resting in the little hole on the pot pin but wasn't soldered - if you remove the head from the combo chassis it's the right most wire if you're looking at the board from the back.
I called Mesa to see if this was normal since it seemed odd that the assembly tech would miss the same wire on two pots. They checked and confirmed that of course all three wires should be soldered down. I get "permission" from the Mesa tech to solder the wire without violating my warranty, 3 minutes and a little bit of rosin core solder and the static was gone -- turns out the vibration from the bass notes was shaking the circuit board just enough to cause those two wires to lose contact with the pots!
I'm not grinding on Mesa - I love the amp and love that it was actually hand built in the USA. I traded in a Marshall DSL15C for the 5:25+ and it was one of the best decisions I've made - I love this amp at bedroom practice levels on the 5W setting on both channels (even late at night when the kids are asleep), and it get's plenty loud with great tone to keep up with a drummer at the 15W setting, and at the 25W setting it's louder than I would need for any venue I'll get invited to play at. Super convenient weight too.
Rock on!
