Tubes - Who Wants to Talk About Quality Control???

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CHIP
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by CHIP »

briane wrote:
May I add, Why can't a tube manufacturer produce tubes with NOS quality and sound?
blame the laws that keep people from breathing boron gas. Tell, do you just want some poor asian doing for you? no, they outlawed that too.

You and your buddy's did apply for that highly toxic job breathing boron gas, right?

playing with mercury is fun too. not.

making good tubes is very toxic.

I like JJ and EH. still runs about 50%. What do you think fender does? They have a deal to send them back if they suck, and thats why small cant compete when the materials going in are shoddy. If your a business, you HAVE to get the same deal as they do to compete. Exactly why I wont do transistor work anymore, there I run about 19 out of 20 as shoddy.
Just have them wear a gas mask and gloves. Simple solution.
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sharkboy
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by sharkboy »

I neglected to mention that I've been pretty happy with Shuguang tubes, though their EL84s are the only ones i am currently using regularly. I am a bit wary of their rectifiers, so I just have EH and JJs.

I've been doing a bit of a shootout between 6L6/KT66 tubes in my possession in a Dunble clone. So far, I'm quite happy with all but the JJ:

(not scientific, not finished and haven't gotten very loud yet):

1. TS reissue KT66
2. GT6L6-GE
3. SED 6L6
4. Shuguang KT66
5. JJ 6L6
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martin manning
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by martin manning »

CHIP wrote:
briane wrote:
May I add, Why can't a tube manufacturer produce tubes with NOS quality and sound?
blame the laws that keep people from breathing boron gas. Tell, do you just want some poor asian doing for you? no, they outlawed that too.

You and your buddy's did apply for that highly toxic job breathing boron gas, right?

playing with mercury is fun too. not.

making good tubes is very toxic.

I like JJ and EH. still runs about 50%. What do you think fender does? They have a deal to send them back if they suck, and thats why small cant compete when the materials going in are shoddy. If your a business, you HAVE to get the same deal as they do to compete. Exactly why I wont do transistor work anymore, there I run about 19 out of 20 as shoddy.
Just have them wear a gas mask and gloves. Simple solution.
It may not be as simple as a mask and gloves, but hazerdous materials can be delt with. All it takes is money (increased manufacturing cost) which has to be recovered in the sale price.
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briane
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by briane »

It may not be as simple as a mask and gloves, but hazerdous materials can be delt with. All it takes is money (increased manufacturing cost) which has to be recovered in the sale price.
yep, right on - but I cant afford 400$ tubes, or whatever it costs for the environmental cleanup.

we have a saying in software - If we made bug free software it would be so expensive noone could afford to run their computer - its just a hazard of dollars, starving people, and the fact that there just aint (and never will be) enough to go around for all of us - just be glad your still above ground is what I always say - a lot of our former friends are not.

Man can accomplish any task - but is it worthwhile, profitable, and maintainable? - well thats another question.
it really is a journey, and you just cant farm out the battle wounds
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Lynxtrap
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by Lynxtrap »

Here's a rant for you:

I thought about this exact question when I was going to order a couple of 6L6GC's yesterday. You'd think those wouldn't be too hard.
But then I started ruling out the available brands by different criteria.

Shuguang - to cheap, no warranty.
Sovtek - boring.
Sylvania - won't last more than a couple of months, based on experience.
JJ - stiff and too much headroom.
EH - isn't that the same as Sovtek?
Golden Dragon - out of stock.
Groove Tubes - too expensive.

Then there are all those letters and variations. 5881, STR, EH, GA, GC, WGA, WXT, WXT+... And the underlying suspicion that they're all the same with different letters on the box. Since they don't show any datasheets, I won't buy blindly and blow them with 470 pV.

I settled for a pair of TungSol. They haven't arrived yet, so that was fine until I read in this thread that they're shit :roll:
brentm
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by brentm »

Lynxtrap wrote:Here's a rant for you:

I thought about this exact question when I was going to order a couple of 6L6GC's yesterday. You'd think those wouldn't be too hard.
But then I started ruling out the available brands by different criteria.

Shuguang - to cheap, no warranty.
Sovtek - boring.
Sylvania - won't last more than a couple of months, based on experience.
JJ - stiff and too much headroom.
EH - isn't that the same as Sovtek?
Golden Dragon - out of stock.
Groove Tubes - too expensive.

Then there are all those letters and variations. 5881, STR, EH, GA, GC, WGA, WXT, WXT+... And the underlying suspicion that they're all the same with different letters on the box. Since they don't show any datasheets, I won't buy blindly and blow them with 470 pV.

I settled for a pair of TungSol. They haven't arrived yet, so that was fine until I read in this thread that they're shit :roll:
I've tried several. Right now, I like the TAD 6L6GC-STR. I could live with those if I had to, they're Chinese sourced. But ultimately, the Philips 6L6GC-WGB are the best bang for your buck. I've been happy with my Tung Sol reissues too... but after rolling tubes, the Philips 6L6GC-WGBs seem to be the best sounding to my ears.

I think your suspicions on the letters/numbers may be a little off the mark. 5881 and 6L6GC tubes have different ratings with the 6L6GC being capable of higher plate voltage. People much more educated than myself could probably explain this ad nauseum.
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martin manning
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by martin manning »

I really can't find anything all that scary or unusual among the materials used in the manufacuring of vacuum tubes. Radioactive thoriated tungsten was used for some cathodes, but it is also the material used for TIG welding electrodes. The much more common oxide-coated cathode uses a coating made of strontium carbonate, which is used in ceramics and fireworks, along with barium, which is also the metal used in getters. This last element is probably the most dangerous, however until recently it was widely used in CRT manufacturing.
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Reeltarded
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by Reeltarded »

CHIP wrote: Just have them wear a gas mask and gloves. Simple solution.
Like.. eating at Arby's?

I have only recently been stunned by the tube problem. I had been blind to just how bad things were mostly by luck.

I don't have an answer, except use a variac to knock a few volts off so they last longer when you get good ones.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
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Luthierwnc
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by Luthierwnc »

One thing working against us is that in the golden days of tubes, major electronics manufacturers either made their own or had them built to their exact needs. They insisted on excellent tolerances since their brand recognition, repeat business and overall reputation was only as good as the tubes in their products. Westinghouse would crush an entire batch before they would send out TV's with tubes that had poor failure rates.

When I do my BOM, I consider the tubes separately from all the rest of the components. It is Russian roulette whether the thing will red-plate at a gig. I had a JJ 7591 do just that. Reputable vendor too. sh
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SoundPerf
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by SoundPerf »

I always just thought is was a simple matter of built in limitied lifespan. Back in the day when just about every electronic device used tubes the manufactures could afford to make them of the highest quality and to last a very long time becuase there was enough market out there to be still be very profitable. Also, once upon a time the US worker and manufacture prided itself in making completely over-engineered and manufactured products. Unfortunately this doesn't seem to exist anymore.

Now with tubes being pretty much a niche market it's just not profitable to make them to last long and I imagine it is purposeful to a degree to make the coatings of a lesser quality. I find unless there is a significant defect, most new production tubes sound pretty darn good at first, but then quickly fade. The exact milage varies from brand to brand, but pretty much consistent. (and there are some that just don't seem to ever cut it)

Couple in the very possible fact of undedicated workers and the problem is exsacerbated to some greater extent. Personally, I was under the impression that there's enough tube amps being built and used that there is a enough market for it to be profitable and also competitive enough to see better quality overall than less with new production stuff. I mean I remember a period in the early 80's the only tubes I new of were Groove Tubes and I figured sooner or later there wouldn't be anymore tubes at all. (I admit I was pretty much a rookie then)

I've been pretty impressed with TAD and Tung Sol for bang for the buck.
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CHIP
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by CHIP »

I agree Soundperf.
I think the modern tube amp market has grown in the last 20 years, to a point where a manufacturer could be profitable if they could produce a NOS comparable product. Even if they cost a bit more, if you as a customer knew what you where getting you would be willing to pay the additional cost.
brentm
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by brentm »

CHIP wrote:I agree Soundperf.
I think the modern tube amp market has grown in the last 20 years, to a point where a manufacturer could be profitable if they could produce a NOS comparable product. Even if they cost a bit more, if you as a customer knew what you where getting you would be willing to pay the additional cost.
There is enough existing tube manufacturers to dilute the market and discourage new entrants. Really. The existing used, "NOS", and new production tubes are as good as it gets. Even Ei is gone and now only rumors exist on their demise.
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Luthierwnc
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by Luthierwnc »

The difficulty we face as consumers is that there isn't a central clearinghouse for grading; tone, longevity, stability and/or compliance to specs. As quickly as factories, brand names and distribution deals come and go, it is tough to get a read on consistency. I'll read a post that someone loves a new tube and three months later they report that it drifted 17 ma and the coating is flaking off the cathodes.

That creates problems for the supply side of the chain too. It would be risky for a manufacturer to decide; I'll make a 6L6 that is 20% more reliable than X-brand tube and charge 12% more. Pearls before swine unless they have a way to demonstrate the advantage. In my previous post I stated that the big western manufacturers spent a lot on recognition in a competitive market. Eastern block and especially Chinese makers of almost anything have not learned to do that. "Celestial sonic happiness!" doesn't tell me much.

To make matters worse, I am woefully uninformed on the market for audio vacuum tubes. If anyone knows, I'd like to hear the size of the wholesale market and how much the; OEM, hi-fi-, general replacement, boutique (that's us) and other buyers represent. If we are 3% of the gross, we're SOL on driving the bus. If we're 17%, there is probably room for someone to squeeze through if they can demonstrate superior value.

FWIW, I've had good luck with the TADs and Tung Sol RI power tubes. Preamp tubes are kinda all over. I've had three JJ power tube critical failures but those were 3-5 years ago and it could be a completely different animal now.

Cheers, sh
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renshen1957
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by renshen1957 »

martin manning wrote:As always, vote with your $, and reject product that fails to perform. This could mean buying only tested devices or insisting on the option of returning sub-standard parts. Re the 300B, that's a niche within a niche, no? In general there is reason to believe that niche products can survive, and there are many examples today, but a premium will always be required for viability
Hi

To add to what was stated above:

Depends on the Niche and what the market in that niche will bear.

Factor one, Musicians as in Guitar amps that use tubes (unless they are "Stars") generally can't afford a pot to piss in, let alone NOS quality tubes.

Factor Two, Musical instrument tube amplifiers do not drive the market, Hi-Fi Audiophiles do.

Factor Three, The major consumer whores of the world, the US consumer isn't by and large purchasing consumer grade tube electronics or much of anything from the depression the country is in, don't let the spin doctors tell you otherwise. They purchase the latest spin on cell phones, flat screen TVs, computers, which without exception contain overseas manufactured parts and assembled overseas, and are future e-waste for the land fills.

Factor Four, mainland Chinese with their economy at full bore with new found affluence purchase and produce a number of tube amps as well as higher grade tubes if the price is right.

Currently, Shuguang boasts production numbers for 300B (40% of all the 300Bs ever built or some such nonsense), and a number of other Tube companies exist in China, or have recently come into existence to produce Hi-Fi tubes.

Best Regards

Steve
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renshen1957
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Re: Tubes - Who Wants to Talk About Quality Control???

Post by renshen1957 »

Luthierwnc wrote:The difficulty we face as consumers is that there isn't a central clearinghouse for grading; tone, longevity, stability and/or compliance to specs. As quickly as factories, brand names and distribution deals come and go, it is tough to get a read on consistency. I'll read a post that someone loves a new tube and three months later they report that it drifted 17 ma and the coating is flaking off the cathodes.

That creates problems for the supply side of the chain too. It would be risky for a manufacturer to decide; I'll make a 6L6 that is 20% more reliable than X-brand tube and charge 12% more. Pearls before swine unless they have a way to demonstrate the advantage. In my previous post I stated that the big western manufacturers spent a lot on recognition in a competitive market. Eastern block and especially Chinese makers of almost anything have not learned to do that. "Celestial sonic happiness!" doesn't tell me much.

To make matters worse, I am woefully uninformed on the market for audio vacuum tubes. If anyone knows, I'd like to hear the size of the wholesale market and how much the; OEM, hi-fi-, general replacement, boutique (that's us) and other buyers represent. If we are 3% of the gross, we're SOL on driving the bus. If we're 17%, there is probably room for someone to squeeze through if they can demonstrate superior value.

FWIW, I've had good luck with the TADs and Tung Sol RI power tubes. Preamp tubes are kinda all over. I've had three JJ power tube critical failures but those were 3-5 years ago and it could be a completely different animal now.

Cheers, sh
Hi

Hi Fi Audio tubes do indeed drive the tube/valve market.

Most of the recent European tube reissues have been either Hi-Fi power tubes (7591 JJ and EH, 7868 EH) or Brand Names of famous brand name tubes Genelex Gold Lion and Mullard (but do not in every case look like carbon copy of the originals) and the Tung Sol copies which are very close to the originals (5881 and 6550).

I wouldn't disregard the Chinese tubes entirely. The Psvane, (pronounced Pavane), Shuguang Treasures, TJ Full Music Tube Factory and a number of others do produce credible tubes for a price.

The Chinese also produce other audio products that remind me of the UK and US offerings. http://www.enjoythemusic.com/guangzhou_av_fair_2009

Best Regards,

Steve
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