Best power tube for Marshall mini jubilee?

[Jeff13th]

Hello, I like upgrade my power tube for my Marshall mini jubilee, do you have any suggestions?
And why do you recommend this tube for this amp?


Thanks, Jeff!

 

[Loudness250]

New Old Stock, Mullards or Teslas. But they cost a lot.

 

[napalmdeath]

There's no bias adjustment, just so you know. That said, I'd get a warm pair of JJ KT77's. Eurotubes will hand pick a pair that will run in the proper range.

 

[Racerxrated]

Haven't owned a mini, but I had the 2555x for a minute and it didn't react much differently when I tried some of my NOS EL34s. As opposed to the original Jubilees, of which I've had many, those NOS tubes really make a difference for the better. My favorite 34s are Winged C, vintage Mullard and Siemens. New Production I'd say the Tung Sols.

 

[Jeff13th]

There's no bias adjustment, just so you know. That said, I'd get a warm pair of JJ KT77's. Eurotubes will hand pick a pair that will run in the proper range.

You shure KT77 run great on this amp?

On some forum I read that yes no problem because the mini jubilee is a class A amp with a cathode bias and the KT77 are in the same familly of el34 same for 6AC7 are the equivalent with the American name of EL34!

In other place I read that the current plate of a marshall cathode bias would not be suitable for KT777 or 6AC7?

Because on this forum I read this (the mini Jubilee is a 20 watt amp with comme with two Tubes Tungsol EL34's, and plate voltage is 258. However, my calculations put me at around 67mA at 70%, and was only getting 56mA)

On another thread I saw that the plate voltage on the mini was 295V, the both is pretty darn low.

the plate voltage It is ok to run the mini Jubilee with kt77 or 6AC7?

Thanks a lot Jeff!

 

[Jeff13th]

Do you think kt77 gold lion would work properly in a mini jubilee?

 

[napalmdeath]

Because on this forum I read this (the mini Jubilee is a 20 watt amp with comme with two Tubes Tungsol EL34's, and plate voltage is 258. However, my calculations put me at around 67mA at 70%, and was only getting 56mA

If you research the author of that quote, I'm pretty sure it was me!! Yes, I owned one, I had it apart, my findings were all hands-on.

You're fine with any EL34 variant. I tried E34L's, KT77, and other EL34, besides the stock Tungsols. My problem was, none were warm enough to get into range. I intimately returned the amp. I found it's loose character and lack of a bias adjustment deal-breakers. Too spongy for my tastes.

 

[Jeff13th]

Because on this forum I read this (the mini Jubilee is a 20 watt amp with comme with two Tubes Tungsol EL34's, and plate voltage is 258. However, my calculations put me at around 67mA at 70%, and was only getting 56mA

If you research the author of that quote, I'm pretty sure it was me!! Yes, I owned one, I had it apart, my findings were all hands-on.

You're fine with any EL34 variant. I tried E34L's, KT77, and other EL34, besides the stock Tungsols. My problem was, none were warm enough to get into range. I intimately returned the amp. I found it's loose character and lack of a bias adjustment deal-breakers. Too spongy for my tastes.

Ok thanks a lot!

 

[napalmdeath]

Because on this forum I read this (the mini Jubilee is a 20 watt amp with comme with two Tubes Tungsol EL34's, and plate voltage is 258. However, my calculations put me at around 67mA at 70%, and was only getting 56mA

If you research the author of that quote, I'm pretty sure it was me!! Yes, I owned one, I had it apart, my findings were all hands-on.

You're fine with any EL34 variant. I tried E34L's, KT77, and other EL34, besides the stock Tungsols. My problem was, none were warm enough to get into range. I intimately returned the amp. I found it's loose character and lack of a bias adjustment deal-breakers. Too spongy for my tastes.

Ok thanks a lot!

It's cathode-biased/plug & play. The reason I'd call Eurotubes & go with JJ's, is because they have hands-on experience, and know what rating will get you into correct range. The 57mA I was measuring in mine was low/cold, but you could easily buy a pair that's too cold, and with no adjustment, be in the 30's or 40's, and you've wasted your money, and are not up to snuff, performance-wise.

Call them, talk to Eddie, (best Customer Service in the business), and he'll get you the right grade, and help you decide between, EL's, KT's, or 6CA7's.

EDIT: I see you're in Canada?? Tubestore can fix you up, I'd just tell them you need a warmer pair. I'm guessing something in the low/mid 40's rating??

 

[Racerxrated]

Jeff, if you can upgrade to the 100w head that has the ability to run ANY 2 pairs of octal tubes, and can be biased with the adjustment dials on the outside of the chassis so no need to open it up, and it has a chart telling you what to bias each pair of tubes to. All you need is a multimeter.
Just an FYI.

 

[napalmdeath]

Jeff, if you can upgrade to the 100w head that has the ability to run ANY 2 pairs of octal tubes, and can be biased with the adjustment dials on the outside of the chassis so no need to open it up, and it has a chart telling you what to bias each pair of tubes to. All you need is a multimeter.
Just an FYI.

Not sure he's unhappy with the amp, just wants to retube it?

However, the 2555X is a whole other animal, I agree. I honestly couldn't return the mini fast enough.

 

[Jeff13th]

Jeff, if you can upgrade to the 100w head that has the ability to run ANY 2 pairs of octal tubes, and can be biased with the adjustment dials on the outside of the chassis so no need to open it up, and it has a chart telling you what to bias each pair of tubes to. All you need is a multimeter.
Just an FYI.

Not sure he's unhappy with the amp, just wants to retube it?

However, the 2555X is a whole other animal, I agree. I honestly couldn't return the mini fast enough.

I'm really happy with this amp! I wants to retube it because I'm not big a fan of tungsol EL34 to compressed for me!

 

[napalmdeath]

Jeff, if you can upgrade to the 100w head that has the ability to run ANY 2 pairs of octal tubes, and can be biased with the adjustment dials on the outside of the chassis so no need to open it up, and it has a chart telling you what to bias each pair of tubes to. All you need is a multimeter.
Just an FYI.

Not sure he's unhappy with the amp, just wants to retube it?

However, the 2555X is a whole other animal, I agree. I honestly couldn't return the mini fast enough.

I'm really happy with this amp! I wants to retube it because I'm not big a fan of tungsol EL34 to compressed for me!

KT77's will do the trick, or the 6CA7's.

 

[Racerxrated]

Jeff, if you can upgrade to the 100w head that has the ability to run ANY 2 pairs of octal tubes, and can be biased with the adjustment dials on the outside of the chassis so no need to open it up, and it has a chart telling you what to bias each pair of tubes to. All you need is a multimeter.
Just an FYI.

Not sure he's unhappy with the amp, just wants to retube it?

However, the 2555X is a whole other animal, I agree. I honestly couldn't return the mini fast enough.

I'm really happy with this amp! I wants to retube it because I'm not big a fan of tungsol EL34 to compressed for me!

KT77's will do the trick, or the 6CA7's.

I would try and grab a pair of used but strong Siemens 34s, they can be found for 60-80 a pair. They sound great in vintage Marshalls, I'd give them a shot. Winged Cs and especially Mullards even used are too much.

 

[napalmdeath]

Jeff, if you can upgrade to the 100w head that has the ability to run ANY 2 pairs of octal tubes, and can be biased with the adjustment dials on the outside of the chassis so no need to open it up, and it has a chart telling you what to bias each pair of tubes to. All you need is a multimeter.
Just an FYI.

Not sure he's unhappy with the amp, just wants to retube it?

However, the 2555X is a whole other animal, I agree. I honestly couldn't return the mini fast enough.

I'm really happy with this amp! I wants to retube it because I'm not big a fan of tungsol EL34 to compressed for me!

KT77's will do the trick, or the 6CA7's.

I would try and grab a pair of used but strong Siemens 34s, they can be found for 60-80 a pair. They sound great in vintage Marshalls, I'd give them a shot. Winged Cs and especially Mullards even used are too much.

Personally, NOS tubes are overpriced and overrated. I'd never waste money on the hype. Preamp tubes, yes.. Power tubes? No thanks.

 

[Racerxrated]

Jeff, if you can upgrade to the 100w head that has the ability to run ANY 2 pairs of octal tubes, and can be biased with the adjustment dials on the outside of the chassis so no need to open it up, and it has a chart telling you what to bias each pair of tubes to. All you need is a multimeter.
Just an FYI.

Not sure he's unhappy with the amp, just wants to retube it?

However, the 2555X is a whole other animal, I agree. I honestly couldn't return the mini fast enough.

I'm really happy with this amp! I wants to retube it because I'm not big a fan of tungsol EL34 to compressed for me!

KT77's will do the trick, or the 6CA7's.

I would try and grab a pair of used but strong Siemens 34s, they can be found for 60-80 a pair. They sound great in vintage Marshalls, I'd give them a shot. Winged Cs and especially Mullards even used are too much.

Personally, NOS tubes are overpriced and overrated. I'd never waste money on the hype. Preamp tubes, yes.. Power tubes? No thanks.

That's why I suggested used but strong. Those tubes usually have tons of life left, and in a vintage Marshall they absolutely make a difference. Newer amp? Not sure, but if they are cheap enough it's worth a shot. I would never pay for NOS tubes pre or power, not when you can find strong used versions for 1/10th the price.

 

[guitarexpert224]

If you research the author of that quote, I'm pretty sure it was me!! Yes, I owned one, I had it apart, my findings were all hands-on.

You're fine with any EL34 variant. I tried E34L's, KT77, and other EL34, besides the stock Tungsols. My problem was, none were warm enough to get into range. I intimately returned the amp. I found it's loose character and lack of a bias adjustment deal-breakers. Too spongy for my tastes.

Old past but this amp has no sponginess to it. You most likely didn't dial it in properly. Output Master has to be at least at 7, and input gain shouldn't be any higher than . It's really tight. , if you go any highter than 6 on the input gain it gets spongy. Most don't know how to dial in this amp.

 

[napalmdeath]

Old past but this amp has no sponginess to it. You most likely didn't dial it in properly. Output Master has to be at least at 7, and input gain shouldn't be any higher than . It's really tight. , if you go any highter than 6 on the input gain it gets spongy. Most don't know how to dial in this amp.

Yes, I had a second go at it, and did indeed figure it out.

I had 3 other amps when I owned it the first time, and didn't really spend a lot of time with it. Second time, I dialed it in nicely. The key is to not use the rhythm clip on the lead channel. Open it up with the masters, and hit it with a boost. Its a killer amp.