Problem ;-(

syscokid said:
Changing the capacitor in this scenario does not make sense to me. Changing a resistor, especially the resistor that sets the bias, is probably more likely what happened in your amp. The new bias resistor probably increased the bias of your amp. Therefore, the power tubes are running cooler... more headroom... punchier.

Anyways... whether it was a replaced cap, or a replaced resistor, or maybe your friend spilled some cold beer on it, I'm glad your amp is working better now. And, you didn't even electrocute yourself either... :cheers:
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Ya, way above my head. I just stuff tubes in and roast them....

Tubes!.JPG
 
67plexi said:
Looking back EL84 failed tubes was the issue on the last 5 blues JR amps I looked at. I only have two amps that use EL84's this is the only EL84 I will use in my amps
it can take 450v and last 5,000 hours. https://www.tubedepot.com/products/sovtek-el84m-power-vacuum-tube
I got a box of 50 direct from Russia they are not made now so get them while you can.
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Given the original tubes were running too hot and they lasted over 2 years yesterday I did ask the tech about tube quality and longevity. He suggested with the quality of his replacement and the domestic use (not driven very high) situation they should last many many years. I don't think a box of 50 would work for me :-)
 
HEY CHAS

...is that this one???
CLEARANCE- Vintage16 5 Watt / 16 Watt Triode Amp

Vintage_16-5_2048x.jpeg
 
Robert Herndon said:
tubes-jpg.11524
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That is such a beautiful sight... it brings some tears to my eyes... :cry:

gasket said:
Given the original tubes were running too hot and they lasted over 2 years yesterday I did ask the tech about tube quality and longevity. He suggested with the quality of his replacement and the domestic use (not driven very high) situation they should last many many years. I don't think a box of 50 would work for me :)
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Hey... Two years for EL84s in top shape, in an amp that gets used a lot, is pretty good. It's worth investing in some good stuff while it's still around.

eSGEe said:
...is that this one???
CLEARANCE- Vintage16 5 Watt / 16 Watt Triode Amp
Click to expand...
These normally sold for $500, I think. It'll be interesting what the clear-out price is going to be.
 
I have a pair of 6p14p, but not the EV (EB?) military variant.
They are being run push pull cathode bias at right around 100% plate dissipation at a plate voltage of 316v.

I know plenty of tubes are run way above the max spec plate voltage with a decent service life, but read these typically dont last long above the 250v spec. max.
I did not know this until after, but they were dirt cheap.

They sound really good and I'm on the hunt again for the more rugged EV variant.
 
Looks like 329 volts B+1 on the blues JR http://ampwares.com/schematics/blues_jr.pdf That explains the five I worked on with power tube failed with 300v max on the tube data.

I have Trainwreck Rocket and a EF86 18 watt both are 310 volts so the military EL84M have to be used they can take 450 volts max.

If you can find NOS 7189A 440 volt max that will work.
 
IMG_7254.JPG IMG_7336.JPG IMG_7343.JPG I have a 15 watt Weber Attenuator for the Monoprice, that is great to get it in the over driven state. That thing on top of it goes in and out of the effects loop to turn the volume down when the amp is near 10, I bought it for my Hot Rod Deluxe. I use only a few pedals in front of it. The train is how things are going.
 
I'm going to have to try some variants other than the JJ's I've been using. I have good luck-usage with them, but open to try something else. My Peavey Delta Blues got a new matched set when I bought it used, & my two MP 15's are still running on the stock Chinese tubes, but non of mine are running hot like the Blues Jr's do.
 
Ultra80096 said:
I'm going to have to try some variants other than the JJ's I've been using. I have good luck-usage with them, but open to try something else. My Peavey Delta Blues got a new matched set when I bought it used, & my two MP 15's are still running on the stock Chinese tubes, but non of mine are running hot like the Blues Jr's do.
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JJ's are a good tube. The 7025-WA's (pre amp tubes) are smoothest and quietest and the Genelex Gold Lion T12AX7 has the most gain...as far as power tubes go, the KT88 is a nice one...but what are you looking for??? The differences are very subtle...what tube #'s are you using currently???
 
I remember that train wreck - Chatsworth, California September 13, 2008. No one in the Pomona dispatch center noticed two trains on the same track. The engineer of Metrolink 855 sent/received an enormous amount of text messages in the 20 minutes leading up to the 4:16pm crash.

He failed to observe a red signal and due to a curve in the track, neither engineer could see the approaching train until only 5 seconds before the crash.

The trains struck head on at 40mph each - 80mph impact speed. Out of 225 people on board, only 25 died...amazing.

Consider Casey Jones' April 30, 1900 fatal crash at Vaughan, Mississippi at 3:52am. He was able to slow #382 from 75 to 35mph before impact - engineer Jones was the only casualty - and Casey threw his fireman Sim Webb from the cab only seconds before.

Several cars full of corn were destroyed on impact - and an unexplainable patch of wild corn still grows there to this day...

I've stood there in the Summer of 1980...
 
Robert Herndon said:
.

Consider Casey Jones' April 30, 1900 fatal crash at Vaughan, Mississippi at 3:52am. He was able to slow #382 from 75 to 35mph before impact - engineer Jones was the only casualty - and Casey threw his fireman Sim Webb from the cab only seconds before.

Several cars full of corn were destroyed on impact - and an unexplainable patch of wild corn still grows there to this day...

I've stood there in the Summer of 1980...
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A fitting memorial I would say.
 
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