Friggen' tubes

[warnergt]

Tubes definitely aren't what they used to be. I believe I am done with
tube amps.

Our guitarist is having problems with his Marshall. I agreed to check it out.
It just so happens that I have a tube tester so I check the tubes.
I found one of the four ECC83/12AX7 tubes to be bad.

No problem. It also so happens that I have a brand new 12AX7 in the
box which was a spare for my SVT-3 PRO. However, I check it first.
You probably already guessed it -- it was bad, too.

I don't believe that there is any form of real quality control on tubes
manufactured today. They ship anything.

[NecroticImbecil]

My friend's car got a blown out tire. I was going to let him use my spare, but it was flat. I'm done with cars.

[AlPBass]

Most things aren't what they used to be these days. I'm not old enough to have seen the 60s, 70s and early 80s stuff firsthand, so I'm no expert on this issue. But nevertheless, everybody seems to be cutting corners left and right now and lots of stuff I've seen in stores the last few years definitely looks subpar, especially electronics. I've been lucky to not have experienced major defects/failures with any of the more expensive things that I've bought, but I know people who weren't so lucky. A friend of mine bought a Les Paul and a Blackstar tube amp recently: buttons cracked on the Les Paul and the nut had to be adjusted, and the amp fried the day after he got it.

[greenboy]

There have always been bad tubes, though. People like to forget that, but I remember.

[RadioPilot]

It's just bad luck. There are worse problems to have when it comes to tube amps...

[BurningSkies]

Originally Posted by greenboy

There have always been bad tubes, though. People like to forget that, but I remember.

I have a few of those new fangled NOS RCA blackplates, 6v6's, 6L6's and 12AX7's...damned if at least one or two of each isn't microphonic or just bad. They sure don't make them like they used to...

[Jim C]

Originally Posted by greenboy

There have always been bad tubes, though. People like to forget that, but I remember.

Agreed, but I am having amazingly good luck using old Mullard and Telfunken 12AX7's borrowed from 70's Eico and Dynaco gear.
Even bought a couple on eBay that sound very good.

[JazzbassArt]

Dam, none of the tubes in my QSC have given me grief.

[96tbird]

I love tubes. And I'm cheap and reckless.

The cheap part: I buy 4 unmatched Soviet surplus 6p3s-e tubes with the coin base, which cost me a bit over 8 bucks a piece to my mailbox. I have done a lot of research on them and some say they may handle the 540 plate volts on my '74ish V4-B, some say no.

http://www.auctiva.com/hostedimages/...0,0,0&format=0

The reckless part: No rebias; plug them into my amp and hit the power, leave standby off and watch for filament burn and keep touching them to see if they get too hot. After 10 minutes I hit the standby and flood the plates with 540 volts. start playing softly and watch them for redplate, start hammering them cranking the volume and bang them around for 45 minutes. no sign of trouble and I can hold my finger with little sensation of heat on the bottom 1/4 of the valves: they hang down in the 'peg. of course the upper 3/4 is too hot to touch for long.

They sound outstanding. there is no sign of microphonics, gas glow, any of the bad stuff. They sound incredible, tight and warm and bright. My old Magnavox 7027a's will be retired as backups and I will order another set of 6p3s-e's for cheap.

[T-Bird]

Hi.

OP, I kind of feel Your pain, but, there's one huge fail in your post. IMHO anyway.

WHAT were the bad tubes?

That, in my book anyway, makes a huge difference.



I'm also not old enough to have witnessed the heyday of tube gear, but some of the friends I have are. They clain that the cheapo tubes of yesteryear were worse than the cheapos we have now.

The good ones were alsso much better than the good ones we have ATM they say, but often one could buy 10 cheapos for the price of one quality tube. Out of those 10, at least 2 were DOA, and at least 6 gave a long service, comparable with that one quality tube.

Regards
Sam

[runmikeyrun]

i've used JJs with no ill effects for many years now. Maybe it's time to switch brands.

Jim C, nice triple! I had a 76 KH 400, and own/have owned several Yamaha RDs. Love them two smokers!

[metalmariachi]

LOL
In the ‘50s and ’60 every drug store had a tube tester in it.
So did a lot of the Sears and Wards stores.
Rat Shack and Heathkit stores were electronics tube heaven.

When some thing (radio, TV or amp) didn’t work you pulled all the tubes, took them down in a brown paper bag and tested them.
Bought new ones to replace the blown ones.
Matched power tubes? If one was bad you bought one.

Yup those $2.00 RCAs were way expensive.

Seen an IC tester lately? It’s a tad more difficult to just swap one of those out.
Or even sourcing one for your MINI Brute.


MM

[96tbird]

Originally Posted by metalmariachi

LOL
In the ‘50s and ’60 every drug store had a tube tester in it.
So did a lot of the Sears and Wards stores.
Rat Shack and Heathkit stores were electronics tube heaven.

When some thing (radio, TV or amp) didn’t work you pulled all the tubes, took them down in a brown paper bag and tested them.
Bought new ones to replace the blown ones.
Matched power tubes? If one was bad you bought one.

Yup those $2.00 RCAs were way expensive.

Seen an IC tester lately? It’s a tad more difficult to just swap one of those out.
Or even sourcing one for your MINI Brute.


MM

See, that's what i remember with dad and the TV when I was like 5, I couldn't see anyone worrying about matched valves when my head was new and I couldn't see why I should bother now. These russkie tubes I have are mil spec, dated 1981 right on them, the best the russkies had. Severe duty design for use in Mig's, Bear bombers and submarines. Every guy I ever meet who hears my amp wants to buy it. Tubes are IT. Get NOS Russkie for power! Load up while they are cheaper than new production. For pre circuit, JJ has a good rep, but with a little investigation it is possible to find Soviet mil spec analogues for cheap.

[96tbird]

Here, look at these Fender stock 6l6's/5881's http://lh5.ggpht.com/_K51BJD68uqQ/TP...whxTt4/6l6.jpg

http://www.auctiva.com/hostedimages/...0,0,0&format=0

compare them to the russkie's I have. They are identical except for the base and production date Oh and the price.

[warnergt]

Originally Posted by NecroticImbecil

My friend's car got a blown out tire. I was going to let him use my spare, but it was flat. I'm done with cars.

Interesting analogy but I didn't say I was done with amps; I said I was
done with tube amps. There is an alternative to tube amps. I know of
no alternative for tires on cars.

I realize that having a bad item and a bad spare sounds like a
statistically rare scenario. But, from my experience, I would bet my
bottom dollar that I can find a much higher percentage of bad tubes new
in the box than bad new spare tires.

[audiomitch]

Originally Posted by Jim C

Agreed, but I am having amazingly good luck using old Mullard and Telfunken 12AX7's borrowed from 70's Eico and Dynaco gear.
Even bought a couple on eBay that sound very good.

Since those old tubes survived to today, they were good tubes back then. A bad tube in any of that old gear would have been replaced in the '70s. The ultimate tube tester - the test of time.

[warnergt]

I've serviced a lot of tube amps, stereos, radios and even some tube TVs
back in my early days. Yes, tubes have always been subject to failure.
When I serviced any tube equipment, the tubes were always the first
components to be suspect.

I don't service equipment nearly as much these days. It's usually
something of my own or something for a close friend or something I'm
just curious about. It's hard to draw conclusions from a limited sample
set but I think the trend is clear. I don't recall ever buying a new
tube and finding it to be bad until recent years. Over and over and over,
I see brand new rigs with tube failures in less than six months.

Your mileage may vary but that's my perspective.

[ThatBassistDude]

Originally Posted by NecroticImbecil

My friend's car got a blown out tire. I was going to let him use my spare, but it was flat. I'm done with cars.

+50,000

[seamonkey]

Originally Posted by warnergt

Interesting analogy but I didn't say I was done with amps; I said I was
done with tube amps. There is an alternative to tube amps. I know of
no alternative for tires on cars.

I realize that having a bad item and a bad spare sounds like a
statistically rare scenario. But, from my experience, I would bet my
bottom dollar that I can find a much higher percentage of bad tubes new
in the box than bad new spare tires.

So a car analogy It's like getting low compression on one cylinder. The car still runs, the compression went bad over time and you just don't notice it until you take it in for service and they want to charge a bundle to fix it. And you can't believe it's that bad because it seemed to run fine.

There's no tube testers around anymore, more than likely there's a lot of sub par performance that they can't check. Even many techs don't have tube testers.

And forget buying NOS to capture quality. It's full of counterfeits because no one can actually tell by looks or a box.

I saw a old picture of bad tubes coming out of a factory line and getting put through a shreader/crusher. I can bet that no tube factory today does this. They just don't label them. These sub par Somehow end up on the market labeled real or fake. And no-one with a tester to check them.

The good news is that software modeling companies have imaged golden versions of amps. They have archived these for anybody to play and a much reduced price over the originals for years to come.

[KLEIN]

Originally Posted by warnergt

I've serviced a lot of tube amps, stereos, radios and even some tube TVs
back in my early days. Yes, tubes have always been subject to failure.
When I serviced any tube equipment, the tubes were always the first
components to be suspect.

I don't service equipment nearly as much these days. It's usually
something of my own or something for a close friend or something I'm
just curious about. It's hard to draw conclusions from a limited sample
set but I think the trend is clear. I don't recall ever buying a new
tube and finding it to be bad until recent years. Over and over and over,
I see brand new rigs with tube failures in less than six months.

Your mileage may vary but that's my perspective.

I switched from SS ampd to tube amps because I kept burning up the transisters.