At this point none of us expect to see the word "easy" and Mesa in the same sentence! As for tantalum capacitors, their main Achilles heel is that they're even more sensitive to damage from brief voltage-reversal pulsing than electrolytic caps are. Tantalums were once extensively used in solid state Hifi gear because when they're new they have very low leakage, but high quality electrolytics nowadays can have equally low leakage. I've replaced many many many small tantalum caps with Panasonic electrolytics and never had a problem.
@@aharkness5657 , Interesting; I've never had one fry right in front of me and so I never smelled the stink. I *have* seen and smelled the rotten-egg aroma of a selenium rectifier burning up, uggh!
I fixed my Mesa Subway Blues myself! After multiple trips to good service techs I unplugged the speaker in the Mesa and plugged it into a cheap Fender amp. At last I can enjoy the sounds from my Mesa amp without all the horrible buzzing, etc.!
This just happened to me during an Express 5:25 repair. That exact tantalum cap (C36) released the magic smoke. I've done a similar repair as you've shown, although I'm trying to swap out the larger C50 cap as well just to be sure it wasn't damaged in the process. Accessing the underside of the board is a total pain though!
Have you ever worked on a Mesa that has sort of a constant cracking/Staticky sort of sound? Like I have a couple Mesa’s that are doing it, (A Blue Angel and an Express 5.50, and even with the volume down and no guitar plugged in you can just hear the cracking/staticky sound. Also the noise doesn’t get louder as you turn the amps volume up, just kinda stays the same in the background. Any idea what could cause that ? I know it’s hard to say exactly, but just mostly wondering if you’ve encountered that issue, and I’d so what caused it or some things that might cause it? Cheers!
I have an express 5/50 and have the exact same problem. I read on a mesa forum that it’s common for the 5/25’s and 5/50’s. If you’re playing at volume it’s not an issue, but it’s definitely annoying. I’ve done the same as another poster above and unplugged the speaker from the mesa head and have plugged it into a $100 Orange micro dark terror. It sounds awesome.
@@Tofino888 Not an issue lol? I dunno if were talking about the same issue then hah. I've been talking with some people, and seems like it's probably some resistors somewhere, like the grid resistors, or something. Mesa uses certain components that are rated for less than the actual Voltage going through them so they often fail, or go bad easily. But yeah, with mine they are basically unusable, unless you wanna hear hum, and pops in your signal.
Question- what is that long bolt for toward the bottom of the shot, below the PCB? Your pokin stick bumps it at about the 2:15 mark. My Lonestar has this but it’s just there, not really holding anything in place. Does it need to be there or can I remove it?
It's a tension screw. Just screw it up by hand until it stops against the top of the cab. It stiffens the chassis and helps stop vibrations and rattles due to the proximity of the speaker in the combo.
I will use tantalum caps, but I use at least a +100% safety factor for the voltage ratings. For the life of me, I don't know why Mesa cuts it so close on ALL of their capacitor voltage ratings. They charge enough money for their overpriced junk.
At this point none of us expect to see the word "easy" and Mesa in the same sentence! As for tantalum capacitors, their main Achilles heel is that they're even more sensitive to damage from brief voltage-reversal pulsing than electrolytic caps are. Tantalums were once extensively used in solid state Hifi gear because when they're new they have very low leakage, but high quality electrolytics nowadays can have equally low leakage. I've replaced many many many small tantalum caps with Panasonic electrolytics and never had a problem.
They do also stink when fried.
@@aharkness5657 , Interesting; I've never had one fry right in front of me and so I never smelled the stink. I *have* seen and smelled the rotten-egg aroma of a selenium rectifier burning up, uggh!
I have to say thanks to your videos I've ended up looking at either a Friedman Small Box, a Orange Rockerverb Mk III or a SLO 30.
I fixed my Mesa Subway Blues myself! After multiple trips to good service techs I unplugged the speaker in the Mesa and plugged it into a cheap Fender amp. At last I can enjoy the sounds from my Mesa amp without all the horrible buzzing, etc.!
Thank you for posting.
This just happened to me during an Express 5:25 repair. That exact tantalum cap (C36) released the magic smoke. I've done a similar repair as you've shown, although I'm trying to swap out the larger C50 cap as well just to be sure it wasn't damaged in the process. Accessing the underside of the board is a total pain though!
Held it together with that Mesa! Haha.
I love those small rainbow sausages/ Always did. Always will. No idea what they even are but I've seen them many times and they are too cute xD
I have the 550 plus and its a great amp but has had this same problem twice over 8 years
Is there a place to find descriptions/meanings of the relay designations in the schematic: RYTS; RYOD; RY2; RYE, RYA, etc?
I had one of these. Never sounded that great.
good mesa power tubes? I used to have mesa's 2003-4? can't recall, they were horrible
what is the uf value of the tantalum cap you replaced?
Do you have any sound demos with this amp on your channel? I think I'll try to dig a video when you first changed those 6L6s
I always thought those particles inside the tubes was just mica particles separating from the spacers.
Have you ever worked on a Mesa that has sort of a constant cracking/Staticky sort of sound? Like I have a couple Mesa’s that are doing it, (A Blue Angel and an Express 5.50, and even with the volume down and no guitar plugged in you can just hear the cracking/staticky sound. Also the noise doesn’t get louder as you turn the amps volume up, just kinda stays the same in the background. Any idea what could cause that ? I know it’s hard to say exactly, but just mostly wondering if you’ve encountered that issue, and I’d so what caused it or some things that might cause it? Cheers!
I have an express 5/50 and have the exact same problem. I read on a mesa forum that it’s common for the 5/25’s and 5/50’s. If you’re playing at volume it’s not an issue, but it’s definitely annoying. I’ve done the same as another poster above and unplugged the speaker from the mesa head and have plugged it into a $100 Orange micro dark terror. It sounds awesome.
@@Tofino888 Not an issue lol? I dunno if were talking about the same issue then hah. I've been talking with some people, and seems like it's probably some resistors somewhere, like the grid resistors, or something. Mesa uses certain components that are rated for less than the actual Voltage going through them so they often fail, or go bad easily. But yeah, with mine they are basically unusable, unless you wanna hear hum, and pops in your signal.
Question- what is that long bolt for toward the bottom of the shot, below the PCB? Your pokin stick bumps it at about the 2:15 mark. My Lonestar has this but it’s just there, not really holding anything in place. Does it need to be there or can I remove it?
It's a tension screw. Just screw it up by hand until it stops against the top of the cab. It stiffens the chassis and helps stop vibrations and rattles due to the proximity of the speaker in the combo.
I will use tantalum caps, but I use at least a +100% safety factor for the voltage ratings. For the life of me, I don't know why Mesa cuts it so close on ALL of their capacitor voltage ratings. They charge enough money for their overpriced junk.
MESA "boutique" quality strikes again.