Considering Re-Tubing

[Wakester]

So I am considering Re-Tubing the Used Sonzera 20 that I picked up a few months ago. I have a lead on 3 sets from the same distributer but have some questions that maybe my fine friends can possibly answer before I pull the trigger.

- Is there any real difference between JJ's, SovTek or Tung-Sol? I realize the SovTek's and Tung-Sols are made in the same factory, but do they sound different from each other?

- Does position of the amp make a difference on tube function? I have been using the amp on a kick back stand and it seems noisier tilted compared to true upright.

- Is there a way to safely discharge the capacitors before sticking my hands in the cabinet? Do I really need to worry about that? I've been shocked one too many times, so I worry about that.

Is there anything else I should know about other than biasing the power section?

 

[László]

So I am considering Re-Tubing the Used Sonzera 20 that I picked up a few months ago. I have a lead on 3 sets from the same distributer but have some questions that maybe my fine friends can possibly answer before I pull the trigger.

- Is there any real difference between JJ's, SovTek or Tung-Sol? I realize the SovTek's and Tung-Sols are made in the same factory, but do they sound different from each other?

This is just an opinion based on personal experience, from a person who's into NOS tubes, and obviously I'm not a professional tube tester:

Yes, there's a difference between these tubes. I've used all three.

I find that the JJs are superior to the other two labels. JJ is essentially the Tesla factory, who have always made quality tubes. I find that they have better build integrity, last longer, and have the least noise of any currently made tube.

The Tesla factory has a long history of quality production, and the people running it actually seem to have a clue about how to construct a quality tube - by that I mean, they tend not to go microphonic, and I've had the fewest problems with tube rattle with them. I also think they sound very good.

I had good luck with Tung-Sols in one of the last Two-Rock amps I bought around 2010. It was stocked with them from the factory. They ran out of NOS tubes, and I found these to be a good sounding compromise, though I still prefer JJs.

The Sovtek I found to be pretty generic, and more prone to failure, though less so than Chinese product.

Does position of the amp make a difference on tube function? I have been using the amp on a kick back stand and it seems noisier tilted compared to true upright.

It may, because on most modern production tubes, the mica spacers are not properly set off from the glass with little "fingers", as with NOS tubes or some of the better modern tubes. So due to gravity, there may be more of a tendency for the internal components of the tube to vibrate against the glass, and of course, this will cause noise.

I do find the Eurotubes damping rings to be effective with power tubes, and those are the ones most likely to rattle against the glass due to the size of the internal components. I haven't tried them with preamp tubes, but generally, preamp tubes on many amps are installed with metal, spring-loaded, covers.

 

[Wakester]

Thanks Les, I knew you would have an answer. The JJ's are priced considerably below the other two. I will probably give them a go.

 

[László]

Just for grins, I found this short article on JJ contintuing the Tesla manufacture:

https://www.effectrode.com/news/tesla-heritage-jj-tubes-modern-tube-manufacturer/

 

[László]

Thanks Les, I knew you would have an answer. The JJ's are priced considerably below the other two. I will probably give them a go.

I didn't even know they were cheaper! Perhaps that's because they're not Russian tubes re-branded for a US company that has to take its cut.

So much the better.

And how can I resist an historical note? I can't.

Until the destruction of WWII, Czech manufacturing and tooling was considered equal to anyone's in the world, and The Skoda works was one of the world's premier munitions and auto makers. This isn't to take anyone else's skillset away, but it's no accident that Tesla's tooling and manufacture met high standards, and apparently, JJ has continued that since they use the same machinery.

When it comes to analog equipment, how it's made matters.

 

[Wakester]

I didn't even know they were cheaper! Perhaps that's because they're not Russian tubes re-branded for a US company that has to take its cut.

So much the better.

$102 for the JJ's, vs. $114 for the Sovteks and $122 for the Tung-sols. Sounds like a bargain to me.

 

[László]

$102 for the JJ's, vs. $114 for the Sovteks and $122 for the Tung-sols. Sounds like a bargain to me.

If you agree with my findings when you install the JJs, you can take part of the twelve or twenty bucks you saved and buy me a beer.

 

[Em7]

I agree with Les. JJ/Tesla tubes are the best current production tubes. I have had a pair of Tesla EL84s in a cathode-biased amp that I designed and built in 1997 that are still going strong. They have a much fatter midrange than most other current production EL84 tubes. They sound much closer to an EL34 than most other EL84 tubes.

 

[Wakester]

If you agree with my findings when you install the JJs, you can take part of the twelve or twenty bucks you saved and buy me a beer.

For what I am saving, I'll send you 6 pack. it might be Milwaukee's Best, but it will be a 6 pack.

 

[László]

I agree with Les. JJ/Tesla tubes are the best current production tubes. I have had a pair of Tesla EL84s in a cathode-biased amp that I designed and built in 1997 that are still going strong. They have a much fatter midrange than most other current production EL84 tubes. They sound much closer to an EL34 than most other EL84 tubes.

Amazing that a pair of EL84s have lasted that long!

Looking inside JJ tubes with a magnifying glass, the build quality and assembly seem much more like NOS than current Russian or Chinese offerings. Looks like they're built to a higher standard in all respects.

I claim no expertise, but they do sound good.

 

[László]

For what I am saving, I'll send you 6 pack. it might be Milwaukee's Best, but it will be a 6 pack.

Ha! I don't drink that much beer before it'd get stale. You'd have to help me finish it. so one day, let's just hoist one together!

PS - Milwaukee is fine with me.

 

[Deleted member 5962]

Maybe too late or whatever, but here is what I know, mixed with the advice of the two main tube guys at TGP.

Tung Sol is the most universally recommended new tube for V1 positions. Clearer and more top end than JJs, maybe a slight mid dip.

Tung Sol should NEVER be used in a cathode follower position. V1 is always safe, but the other slots it depends on the amp and I don't know if that amp has any that are cathode followers. Ask PRS, or just don't use one after V1.

The Sovtec 12ax7 LPS is the most universally recommended new tube for the PI slot.

While every amp is different, Doug from Doug's tubes said his most popular recommendations are Tung Sol V1, LPS PI and all the rest depends on the amp.

 

[Deleted member 5962]

P.S. you may try looking on Doug's Tubes site, because he has recommended tube sets for MANY popular amps. I don't know if he has one for Sonzera or not.

 

[Wakester]

I ordered a complete set of JJ's from Audio Tubes Direct via Reverb. The price was right, and they have a lot of good reviews. They shipped USPS this morning from Roebuck SC. I should have them Monday, but will not be able to do any install until the next weekend, as I am on the road yet again M - F.



Have I told you how much I hate living in a Hotel/

 

[László]

Maybe too late or whatever, but here is what I know, mixed with the advice of the two main tube guys at TGP.

Tung Sol is the most universally recommended new tube for V1 positions. Clearer and more top end than JJs, maybe a slight mid dip.

Tung Sol should NEVER be used in a cathode follower position. V1 is always safe, but the other slots it depends on the amp and I don't know if that amp has any that are cathode followers. Ask PRS, or just don't use one after V1.

The Sovtec 12ax7 LPS is the most universally recommended new tube for the PI slot.

While every amp is different, Doug from Doug's tubes said his most popular recommendations are Tung Sol V1, LPS PI and all the rest depends on the amp.

I will disagree with the TGP 'wisdom' here. I was a TGP member for a long time, and remain good friends with the owners of the site, so I have no axe to grind.

To call TGP a serious tool for researching tone is...well...probably not a good idea.

Tung-sol does not remotely compare to NOS in v1, and is certainly no improvement over JJ in v1.

I like the JJ 803S among modern tubes for the PI slot. It's got some nice gain, and does very well in that position.

Hey, no one has the same taste. We're all different. But so many of the folks on TGP don't know WTF they're talking about. People on the internet are just people with the same frailties and lack of knowledge as the rest of us, and most of them aren't exactly mavens on tone. If you want to know what you like, you have to try things yourself.

 

[11top]

If you agree with my findings when you install the JJs, you can take part of the twelve or twenty bucks you saved and buy me a beer.

I’ll even buy you a beer, Les. You know your amp stuff.

 

[Wakester]

About all i know about tubes anymore is to not touch the glass bulbs with your bare fingers when installing them. Something about them prematurely detonating when the oils from your fingers heat up and shatters the glass. I remember watching Dad replacing them in his old Ham radio set, and cursing up a storm when one would blow again.

 

[andy474x]

About all i know about tubes anymore is to not touch the glass bulbs with your bare fingers when installing them. Something about them prematurely detonating when the oils from your fingers heat up and shatters the glass. I remember watching Dad replacing them in his old Ham radio set, and cursing up a storm when one would blow again.

Don't feel bad... but that's mostly BS. I'm not calling you out in any way, internet forums are unfortunately one of the few ways that we have to become "educated" on this basically antique tube technology that is hardly used or talked about any more. There aren't a bunch of authoritative online sources to get this info from, so how are you supposed to know what's what?

I handle my tubes with my bare (clean, but bare) hands, and have had maybe one or two tubes fail due to glass failure/losing their vacuum in the last decade, and I don't think it had anything to do with skin oils. Most of my tube failures are internal component failures. That being said... I would probably be a lot more careful with a $300 NOS tube, but for your stock JJ's and the like, just wash your hands first.

Tung-sol does not remotely compare to NOS in v1, and is certainly no improvement over JJ in v1.

I like the JJ 803S among modern tubes for the PI slot. It's got some nice gain, and does very well in that position.

Hey, no one has the same taste. We're all different. But so many of the folks on TGP don't know WTF they're talking about. People on the internet are just people with the same frailties and lack of knowledge as the rest of us, and most of them aren't exactly mavens on tone. If you want to know what you like, you have to try things yourself.

I would put a little asterisk on this discussion of Tung Sol vs JJ in V1, to say that while I wouldn't definitively state "Brand A is better than Brand B," I do think it matters which specific tube model we're talking about. When it comes to JJ, I've A/B'd with recordings some other tubes against their very common ecc83s (the JJ 12ax7 that comes in many low and mid priced tube amps these days), and while they're rock solid reliable, they don't sound very good. I don't know if it's just because of their gain factor, they seem to have more gain than almost anything else in new production that I've tried, or if there's more to it than that, but they bloat up in the lows especially in V1. The 803s is a great nod though, I've liked it a lot too, as well as their newer grid frame e83cc, which I like the most when it comes to JJ. I'd take a Tung Sol over a bargain bin JJ ecc83s, but I'd also take the JJ 803s or e83cc over the Tung Sol 12ax7.

Back to the Sonzera - OP, have you considered a different tube type altogether for V1? Maybe a 5751 or 12ay7? Those amps, like many of the PRS amps, have a ton of gain on tap. Whenever I've tried a Sonzera, I've wondered what they would sound like with a low gain tube like a 12ay7 in V1. I made that switch in my Sweet 16 and loved the results. Easier to control the gain knob, and more useable throughout the range. In fact, every PRS amp I've owned, with the stock preamp tubes (usually those ecc83s), I have no use for the gain control past halfway, I almost always drop in lower gain tubes of some kind all over the place. There's merit to rolling tubes of the same type to see what you like best, but I get a lot more mileage tweaking an amp's response by using a different tube type altogether.

 

[Wakester]

Back to the Sonzera - OP, have you considered a different tube type altogether for V1? Maybe a 5751 or 12ay7? Those amps, like many of the PRS amps, have a ton of gain on tap. Whenever I've tried a Sonzera, I've wondered what they would sound like with a low gain tube like a 12ay7 in V1. I made that switch in my Sweet 16 and loved the results. Easier to control the gain knob, and more useable throughout the range. In fact, every PRS amp I've owned, with the stock preamp tubes (usually those ecc83s), I have no use for the gain control past halfway, I almost always drop in lower gain tubes of some kind all over the place. There's merit to rolling tubes of the same type to see what you like best, but I get a lot more mileage tweaking an amp's response by using a different tube type altogether.

This being my first foray into tube amps, i just wanted to start with the basics, and get a set of matched tubes to clean up my noise issue. Perhaps down the road, i van start mixing and matcing individual bulbs to refine a sound I like. For the moment though, I don't have much time to tweak, as I am On The Road for work M - F snd sometimes Saturday too.

 

[László]

I would put a little asterisk on this discussion of Tung Sol vs JJ in V1, to say that while I wouldn't definitively state "Brand A is better than Brand B," I do think it matters which specific tube model we're talking about.

I would probably agree.