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Discussion Starter · #1 ·
Hey guys. I noticed two of the tubes in my dual rectifier have been glowing very faintly for a while. The other day one of the them basically stopped glowing (it does a little, but VERY little). There's no loud squeeling or any extra noise, which according to what I've read is usually something I should be getting with a dying powertube. There are four MESA brand 6L6's and then 2 MESA brand 5U4GB's. The 5U4GB's are the ones glowing faintly and then almost not at all. A few times when I've turned the amp on it's been much quieter. (I had it at a quarter volume and it did not sound like the usually stupid loud rectumfrier I love :lol:

Also, I noticed slightly less treble and gain. Although it's still pretty gainy.

The guy that I bought this off threw in two brand new MESA brand 5U4GB's. Should I just replace the troublesome 5U4GB's with these? Or do you guys think it's worth re-tubing the whole thing? If so any recommendations? I like the sound of 6L6's...

I'm guessing the preamp tubes might as well be replaced. Any good Canadian tube distributors?

Here are the pictures, not sure how useful they'll be but it's always better to look at pictures than rely on my shitastic descriptions :lol:

All pictures were taking while the amp was on standby for a good 2 minutes.

The four starting from the right are the 6L6's in this picture.



Another picture.



The 5U4GB's, these are the two troublesome ones.



Everything!



Thanks for the help guys :wub:
 

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The tubes that aren't glowing brightly are rectifier tubes, not power tubes. If you're running the diode rectifier they are doing nothing.
 

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Discussion Starter · #3 ·
Oh ok thank god. Now I feel extra retarded :lol:


What about those volume issues though? It's kind of odd that a few times I've used the amp there have been volume discrepancies. Unless thats perfectly normal?
 

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Those are the rectifier tubes.

Recto guys, can he just switch to diode rectification?
 

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Discussion Starter · #5 ·
I'm using silicon diode rectification. Those pictures were taken with silicon diode on. So I'm totally just really stupid :lol:
 

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Mod Britannia
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OMG, you must replace EVERY tube in the amp right now with "Ultra-Mega-Arse-Rapingly-Expensive" brand tubes. Nothing else will suffice. They have ultra left side tone due to being rolled from flat sheets of glass between the thighs of beautiful Swedish virgins.
 

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They have ultra left side tone due to being rolled from flat sheets of glass between the thighs of beautiful Swedish virgins.
:jj:
 

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The volume issue could be the power or preamp tubes. It's really hard to say. I'd keep an eye on it, and when it happens again report back!
 

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Discussion Starter · #9 ·
Wirelessly posted (A Destroyer of short people: Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_2_1 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8C148 Safari/6533.18.5)

Just played the amp for a good 5 hours. I used the tube rect but there was still a faint glow. It sounded really good though.
 

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From the Grave
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That glow at the top and bottom btw, is the heater coil. Its kinda like the glow plug in a diesel engine. Its there to warm up the tube- the whole reason for standby in a tube amp. Replace the tubes and see if the heater coil lights up in the other set. If neither do, there could be a problem in the circuitry.
 

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I am Groot
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Volume drops, flubby lows, and generally weak tone are all signs of old power tubes. Depending on how long you've had the amp, and how much you (and the previous owner) have been playing it, it might be time for new power tubes. It's good to see that your question got answered, but if you are observing that your amp isn't performing like it used to, then you should consider ordering some new power tubes. Worst case scenario, you try the new ones and notice nothing, and then you can simply store them for the inevitable day that you do need to replace your existing tubes.
 

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Dook dook dook
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Keep an eye on the pre-amp tubes as well, I had a similar problem with the 5150. After a few days one of the tubes was white with oxidations - it was cracked.
 

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I am Groot
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After trying a whole bunch of stuff, I keep coming back to the Mesas. JJs are too dark, Tung Sols are too bright, Electro Harmoinx are wildly inconsistent, and Sovteks are generally shitty. Mesas are the cream of the Ruby crop, since Mesa has first fright of refusal for all tubes Ruby imports, and they have an exhaustive QA process.

Keep in mind that this is from a two guitar band point of view. I love the fundamental sound of JJs, but I find that you get buried under the other guitarist. In a single guitar setting, you'll probably enjoy the extra lower mid beef that they have. I found that a Triple Rec just eats anything that doesn't have enough top end to slice through, and that's what I play against.
 

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Dream Crusher
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Mesa's preamp tubes are lower-gain than normal. Which is a good thing, since Mesas have so much gain to begin with. I use one in V1 in my Budda too to tame it a little bit.
 

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even on the Diode setting, I think the Rectifier tubes do something... a bandmate of mine had a Series I Stiletto Deuce that was blowing fuses like nobody's business, turned out the rectifier tubes were in the middle of dying, even though he was running it on diode rectification.
 
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