"Tube life" Anxiety Caused By Using My Amplifier

[grillebilly]

Believe it or not it’s a common feeling. People buy things all the time and are hesitant to use them for fear of wearing it out. Look at all those low mileage cars and motorcycles in storage. People cover their furniture. The list is endless. I think the realization came to me in my teens that things you love you just need to enjoy as much as possible. Don’t save it for the next guy.
I think in the long run she taught me an important life lesson.

 

[Poultrygeist]

A light bulb is more akin to a vacuum tube than a GTO and will have longer life if not used with a dimmer. Frequent switching on and off is what drastically shortens it's life. Speaking of light bulbs here's a light bulb amp.

 

[TX_Tube]

From a person, far wiser then myself probably said it best.

 

[SWL3600]

If tube life bugs you that much....and I know because I've been there before.....keep your tube gear but have two systems. There's some really good/nice sounding solid state out there.

Using a tube preamp with a solid state amp sounds killer and you don't have to worry about power tubes.

 

[Aerobat]

I worry a bit about this too. I have the original Amperex EL84s in my console pull and I swap in 7189s occasionally to give them a break.

 

[maxhifi]

Thanks guys!

I installed a new capacitor 30,20,20,20uf only several days ago. (Which I did have bypassed internally beforehand)

Original bias caps where 50uf,75v. I replaced with 100uf,200v.

I bypassed the Selenium diode with Silicon 1N4007.

Installed mutch nicer Gold RCA jacks by modifying the original RCA mount to use the ones I had.

I also removed and snipped almost every solder joint. And replaced all the older solder on the PCB with silver solder I had left from my Magnepan repair kit.

Replaced the bias resistors that either had an iffy tolerance, or drifted.

And also replaced both bias Pots with the far nicer/smoother, and more accurate ones from Dynakit.

Also running the amp on 115VAc.

Nice attention to detail, and good job keeping it more or less original - also like the mil spec locking bias pots.

I'll add, if you get yourself a set of Electro Harmonix or Mullard reissue EL34s and GZ34, and a pair of 6GH8A adapters and 6GH8A tubes to plug in for "every day" use, I bet you'll be pleasantly surprised by just how good the new tubes sound. There's a lot of words written online about the superiority of NOS tubes over new ones, but you should take into account a lot of that is based on the awful new tubes we had in the 90s, which really soured a lot of people (myself included!) against the new tubes. Post Soviet Russia was so unstable that their tube quality sharply dropped, and the 90s was when China was not really making any sophisticated products yet. I had new tubes at that time which would arc over and red plate within months of purchase, and was soured for a long time on new manufacture tubes. I've also seen the results of early 2000s era JJ EL34s in an ST70 have runaway bias, resulting in catastrophic failure.

The new tubes of today are way better than what we got 20 years ago, and are good enough that companies like Audio Research, Conrad Johnson and Audio Note use them in amplifiers which are multiple times the cost and performance of the ST-70. I recently got to play with a Conrad Johnson CAV-45 which comes with Mullard reissue tubes, and is a fantastic sounding USA made amplifier, very similar in size and power output to the Dynaco ST-70. With stock tubes it sounded much better than my ST-70 ever did. I also recently retubed an Audio Note OTO SE, and with Electro Harmonix EL84s it was an incredible sounding amp - the original Sovtek (old name for Electro Harmonix) tubes still tested good, and had obviously had 15 years of hard use! The new EL34s are especially rugged because of the abuse they take in guitar amplifier applications. Now while some people may argue that nothing made today beats a Blackburn Mullard from the 1960s, my argument back would be so what? I've heard the new tubes and they really do sound great.

All I'm saying is keep an open mind. I'm presently running Russian Gold Lion KT-88s, after years of NOS tubes in other amplifiers, and I don't see it as a compromise at all. In fact I'm happy to know that if a pair goes south, I can have an identical replacement here within a couple days.

 

[Mr Boochie]

A light bulb is more akin to a vacuum tube than a GTO and will have longer life if not used with a dimmer. Frequent switching on and off is what drastically shortens it's life. Speaking of light bulbs here's a light bulb amp.

Yes! Constant voltage is the key to long, happy electronic life. This is why a good power supply is needed. Try not to turn units on-&-off several times a day.

 

[E-Stat]

But I am having a very hard time just simply enjoying the amp without thinking about every second I use it, (apparently these amazingly georgious tubes inch closer to death.

I'm on my final set of sixteen SED 6550Cs for a pair of VTL MB-450 amps. Those particular tubes are out of production so I will necessarily have to choose something different next time.

Maybe Gold Lion KT-88s that Bea recommends will make me smile more.

 

[E-Stat]

Bust Out Another Thousand.

That's right at what replacing the outputs in my amps runs!

 

[FlaCharlie]

Nice attention to detail, and good job keeping it more or less original - also like the mil spec locking bias pots.

I'll add, if you get yourself a set of Electro Harmonix or Mullard reissue EL34s and GZ34, and a pair of 6GH8A adapters and 6GH8A tubes to plug in for "every day" use, I bet you'll be pleasantly surprised by just how good the new tubes sound. There's a lot of words written online about the superiority of NOS tubes over new ones, but you should take into account a lot of that is based on the awful new tubes we had in the 90s, which really soured a lot of people (myself included!) against the new tubes. Post Soviet Russia was so unstable that their tube quality sharply dropped, and the 90s was when China was not really making any sophisticated products yet. I had new tubes at that time which would arc over and red plate within months of purchase, and was soured for a long time on new manufacture tubes. I've also seen the results of early 2000s era JJ EL34s in an ST70 have runaway bias, resulting in catastrophic failure.

The new tubes of today are way better than what we got 20 years ago, and are good enough that companies like Audio Research, Conrad Johnson and Audio Note use them in amplifiers which are multiple times the cost and performance of the ST-70. I recently got to play with a Conrad Johnson CAV-45 which comes with Mullard reissue tubes, and is a fantastic sounding USA made amplifier, very similar in size and power output to the Dynaco ST-70. With stock tubes it sounded much better than my ST-70 ever did. I also recently retubed an Audio Note OTO SE, and with Electro Harmonix EL84s it was an incredible sounding amp - the original Sovtek (old name for Electro Harmonix) tubes still tested good, and had obviously had 15 years of hard use! The new EL34s are especially rugged because of the abuse they take in guitar amplifier applications. Now while some people may argue that nothing made today beats a Blackburn Mullard from the 1960s, my argument back would be so what? I've heard the new tubes and they really do sound great.

All I'm saying is keep an open mind. I'm presently running Russian Gold Lion KT-88s, after years of NOS tubes in other amplifiers, and I don't see it as a compromise at all. In fact I'm happy to know that if a pair goes south, I can have an identical replacement here within a couple days.

I don't have much experience with newer production tubes and I'm sure you're correct that quality has improved a lot since the '90s and early 2000s. But I still come across reports of problems with recent new production tubes often enough for me to believe that old production tubes are superior.

Unfortunately, many old production types are in short supply and prices have skyrocketed, as you would expect. So, when you factor in price, the "bang for the buck" you get with new production makes sense for most people. I'm cheap. So when I build stuff I look for low cost, NOS alternative tube types. Most people aren't DIYers though, so new production makes sense when cost is a consideration.

The reason companies like Audio Research, Conrad Johnson and Audio Note use new production is simply because they require a reliable supply of tubes. Old production tubes, particularly the most popular types, are not available in large enough quantities or whenever an new order needs to be filled. If they were, I have no doubt those companies would prefer to use them not only for improved performance / reliability but also from a marketing perspective.

Of course the marketing angle has become less of an issue now that several of the famous brand names from the past are being stamped on current production tubes. Sadly, many buyers apparently think they're the same.

 

[FlaCharlie]

I have my Mullard XF3 Blackburns and 7199s Which came with my Dynaco St-70. I love these tubes and think they are absolutely georgious in sounds and looks!!!

And want listen too them, but don't want them to die either..... They are obviously at this point, unobtainable for the unwordly prices they go for.

It's hard for me to get passed that thought while just wanting to listen to music, I want to relax in the music, not stress about its health of the amp.

How can I get past this nonsense?!

Do you worry about wearing out your tires every time you drive?

I don't, but I drive a little Honda Civic and when it's time for new tires I'm always shocked when I see other customers, most of whom drive big trucks or SUVs these days, paying $1000 or more for a set of tires.

You could probably buy a quad of NOS Mullards for the cost of a set of SUV tires. And they will likely last much longer. Maybe if you think of it like that you won't worry about it so much.

Another strategy would be to buy one or two more tube amps (preferably ones that use different tube types) and rotate them. Even if they all have old production tubes, your listening hours will be spread between them so the tubes will be less likely to wear out.

That's probably why my experience with new production tubes is so limited.

 

[Lavane]

I don't have much experience with newer production tubes and I'm sure you're correct that quality has improved a lot since the '90s and early 2000s. But I still come across reports of problems with recent new production tubes often enough for me to believe that old production tubes are superior.

Unfortunately, many old production types are in short supply and prices have skyrocketed, as you would expect. So, when you factor in price, the "bang for the buck" you get with new production makes sense for most people. I'm cheap. So when I build stuff I look for low cost, NOS alternative tube types. Most people aren't DIYers though, so new production makes sense when cost is a consideration.

The reason companies like Audio Research, Conrad Johnson and Audio Note use new production is simply because they require a reliable supply of tubes. Old production tubes, particularly the most popular types, are not available in large enough quantities or whenever an new order needs to be filled. If they were, I have no doubt those companies would prefer to use them not only for improved performance / reliability but also from a marketing perspective.

Of course the marketing angle has become less of an issue now that several of the famous brand names from the past are being stamped on current production tubes. Sadly, many buyers apparently think they're the same.

Other than some EL84's and 6V6's found in old console amps, I've used new manufacture tubes along with a few old stock signal tubes. So far I've only lost two new manufacture tubes. A rectifier and a power tube due to a problem with the amp itself. I think over all they have gotten better. As long as you buy from a reputable source. I stay away from new tubes on eBay and the like due to not knowing if they were made earlier when some manufacturers were having quality issues. I've only run across one new manufacture signal tube that made noise. And even then it did this in one amp only in the voltage gain stage.

 

[Bill Ferris]

That's right at what replacing the outputs in my amps runs!

Yeah, I hear you. B-O-A-T, The same might be said for when the time comes for quality replacement of the (16) KT 88`s, these 4 "space heaters" guys use !

Thankfully, their each are configured for mono in a tri-amp system and only have to process frequencies 80 Hertz on up, and after 10+ yrs. on their original factory tubes, they are still going strong..

 

[TX_Tube]

Now while some people may argue that nothing made today beats a Blackburn Mullard from the 1960s, my argument back would be so what? I've heard the new tubes and they really do sound great.

The best sounding tubes in the World are the 1s plugged into your amp right now, allowing you to enjoy your music selections in the present.

There are plenty of very good tube manufacturers of today, that produce quality products. If 1960 Mullard tubes are out of your price range or unavailable, go find some tubes that are in your wheel house and enjoy using your tube amp, to it's fullest. The only way to derive enjoyment from your system is to actually use it, as often as possible. I run some shug China anniversary KT88 tubes and they sound great to me. YMMV

 

[RS Steve]

Imagine signing up to AK back in late 2011, being afraid to even take a cover off of equipment that is plugged in, and no knowledge of electronics what so ever. Then fast forward to today where I can restore most any piece of tube equipment and some solid state stuff. Everything I know has been learned on this forum, talk about a bit of anxiety when powering up or running some of this gear that I restored myself. I still can't believe I'm capable sometimes, but there is no doubt I have had some great teachers. You just have to remember that back in time all they had was vacuum tube equipment and that it was very reliable. Probably the reason so much of this equipment is still around.

 

[Dr. Ears]

I always buy at least one extra set, but it seems the Chinese are getting better at making output tubes.
You can usually find the NOS input / driver tubes you need.

 

[adrian_zappa]

I sometimes feel like OP, but not so much because of the tubes themselves, it is because in my particular amp it has been impossible to get a schematic or information on how to properly adjust bias and I am afraid when it comes the time to replace the output tubes... But that hasn't stopped me from enjoying the amp at all

 

[FlaCharlie]

I sometimes feel like OP, but not so much because of the tubes themselves, it is because in my particular amp it has been impossible to get a schematic or information on how to properly adjust bias and I am afraid when it comes the time to replace the output tubes... But that hasn't stopped me from enjoying the amp at all

What amp do you have?

You should start a new thread and ask about these issues. Maybe someone has a schematic or experience setting the bias, assuming it's adjustable.

 

[Mr Boochie]

I sometimes feel like OP, but not so much because of the tubes themselves, it is because in my particular amp it has been impossible to get a schematic or information on how to properly adjust bias and I am afraid when it comes the time to replace the output tubes... But that hasn't stopped me from enjoying the amp at all

Bias adjustment should be somewhat straight forward with a fixed bias amp. Adjustment pot(s), onboard dropping resistor(s) or external bias tool, and a volt-ohm meter. Adjustment according to tube type and plate voltage.

Cathode biased amps usually require resistor changes. But, rarely go so far out of spec, that this is needed.

https://www.aikenamps.com/index.php/what-is-biasing

 

[Ivar]

So something has been really driving me crazy!!

And that is using my Tube Amplfier, and finding myself way overally worrying about the tubes on my Dynaco St-70. (Which I fully restored)

I love the sound, and I love everything about tubes and I'm a bit "emotionally" Obsessed with them and get attached.

But I am having a very hard time just simply enjoying the amp without thinking about every second I use it, (apparently these amazingly georgious tubes inch closer to death.

I don't want to worry about such things while trying too enjoy music. I Just want use it and enjoy it.

I have my Mullard XF3 Blackburns and 7199s Which came with my Dynaco St-70. I love these tubes and think they are absolutely georgious in sounds and looks!!!

And want listen too them, but don't want them to die either..... They are obviously at this point, unobtainable for the unwordly prices they go for.

It's hard for me to get passed that thought while just wanting to listen to music, I want to relax in the music, not stress about its health of the amp.

I have a bucking transformer for it too 115VAC, and always Biased too around 1.42V.

But I have all these tubes, and I think about it in my head and go "So in 10x years all these beautifull tubes will all be garbage?" I can't take that thought that this beautifull amp may destroy itself.

How can I get past this nonsense?!

I do have a couple quads of El34s from Nesstone, and Electroharmonex. Both are great working tubes. Its not like I don't have backups. But that's not the point.

My rectifier is a 5AR4 Matshushida also on the amp when I got it, which apparently may outlast me.

I listen to this amp all the time. Everyday.

6BL8 work as 6U8 alternatives aswell I found out.

Use your best tubes now,you only get older and you hearing is getting worse by age.Use the cheap China tubes when you Are old.