1974 Superlead blew a fuse- Bad TAD EL34B

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Mikeyboyeee

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Bastage blew a fuse. Flickering power tube. Swapped an EH EL34 to test with new fuse and played fine.

The El34B is a PC 25 TC 1128.

Worth it to try and find similar TAD rating?
Replace with a matched Quad of Tad's and rebias?
Throw in some JJ kt77s I have a rebias?

Really don't want to have to rebias, but I will if need be.

Any other non NOS, reasonably priced tubes?
 
Bastage blew a fuse. Flickering power tube. Swapped an EH EL34 to test with new fuse and played fine.

The El34B is a PC 25 TC 1128.

Worth it to try and find similar TAD rating?
Replace with a matched Quad of Tad's and rebias?
Throw in some JJ kt77s I have a rebias?

Really don't want to have to rebias, but I will if need be.

Any other non NOS, reasonably priced tubes?
What’s the big deal about re-biasing?
 
It's just a hassle ?.
That being said, the only matched quad I have is JJ KT77.

You know the Amp, any reco on non Mos? What did you have in it? :)
 
Not sure you can even find new tad el34 with the China factory they were made in being no more. The EH el34 is a nice tube for a reasonable price, I would give a quad of those a go. And yes I would check the bias at the very least.
 
Bastage blew a fuse. Flickering power tube. Swapped an EH EL34 to test with new fuse and played fine.

The El34B is a PC 25 TC 1128.

Worth it to try and find similar TAD rating?
Replace with a matched Quad of Tad's and rebias?
Throw in some JJ kt77s I have a rebias?

Really don't want to have to rebias, but I will if need be.

Any other non NOS, reasonably priced tubes?

JJ KT77's are my favorite. Adam Jones likes the Seimens and Mullard XF2's, some say regular JJ EL34's for live. I prefer the fullness of the 77's bottom, mids and top. Pete Diezel does as well. May be a bit too modern for your taste. Good luck!
 
I had three amps red plate power tubes in the last week. Really strange they all did it at the same time.

You are going to need to bias if you change tubes.

I have JJ KT77, Seimens, vintage Mullard XF2 and a lot of other 6CA7 and EL34 tubes around here. The KT77 and 6CA7 midrange is slightly lower and the bass is more like a 6L6. These tubes sound great in a modern amp. If you are overdriving the power amp it is more difficult to control the bass in something like a NMV Marshall.

I'm using EH EL34 in a few of my NMV amps. They sound as good as any of my tubes.
 
I had three amps red plate power tubes in the last week. Really strange they all did it at the same time.

You are going to need to bias if you change tubes.

I have JJ KT77, Seimens, vintage Mullard XF2 and a lot of other 6CA7 and EL34 tubes around here. The KT77 and 6CA7 midrange is slightly lower and the bass is more like a 6L6. These tubes sound great in a modern amp. If you are overdriving the power amp it is more difficult to control the bass in something like a NMV Marshall.

I'm using EH EL34 in a few of my NMV amps. They sound as good as any of my tubes.
Ordered a quad of EHs and also have the JJ KT77s. I'll start with EH. The Amp has been modded of course and has MV.
 
I have the save amp. These days whenever i blow a power tube, I simply replace it with a spare of any brand and as long as it doesn’t red plate & sounds ok , i’m done.
assuming there are no other damage of course.
It crazy to buy four new tubes if only one was bad.
Tubes don’t have to be well matched either. I have a quad of “matched” JJs and one is off by 13 mA. Amp sounds great!
so that spare tube should be fine.
 
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I have the save amp. These days whenever i blow a power tube, I simply replace it with a spare of any brand and as long as it doesn’t red plate & sounds ok , i’m done.
assuming there are no other damage of course.
It crazy to buy four new tubes if only one was bad.
Tubes don’t have to be well matched either. I have a quad of “matched” JJs and one is off by 13 mA. Amp sounds great!
so that spare tube should be fine.
Exactly why it’s worth investing in a tube tester
 
EH EL34 and TUNG-SOL EL34B are what I use and trust. Reasonably priced and reliable.
 
If you have any concerns you can give me a call and I’ll help, the eh will have a lower bias setting than the chinese tubes, I originally sent that amp out with ruby el34b which is the same as the tad.
 
If you have any concerns you can give me a call and I’ll help, the eh will have a lower bias setting than the chinese tubes, I originally sent that amp out with ruby el34b which is the same as the tad.
Thanks. I'm going to take you up on that the next couple weeks.

Thoughts on the ruby's VS EH?
 
Eh is warmer and El34b is brighter, they both sound good and I’ve used them both a bunch, I’m using the eh currently for production, I think they’re the best tubes available today.
Thank you will reach out when they come in and time to bias soon.
 
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