Are Tubes 'consumables'?

Erik Tracy

I'm always 'window shopping' on forums looking at tube gear, but then spotted a statement that tubes only have so many hours on them.

I would guess that older tubes with time already on them would therefore last less? Maybe even a guessing game for when they will 'go'?

How frequently do you toob-heads go thru tubes?

Are they like vintage wines...when the '07 vintage is gone its gone? :cheesygrin:

falconcry72

Yea they're consumables, like batteries.

There are tube testers that can measure different performance aspects of tubes.

Another similarity to wine, is that certain older tube vintages can be better than newer tubes.

heiney9

Absolutely they are consumables. Depending on where and how they are used their life can vary. Typically power tubes give out the earliest but that can also depend on amp topology. Signal tubes can last the longest and even rectifiers like the infamous Mullard 5AR4 can last decades. In general older tubes, since they were made with better care, craftsmanship and especially better and more pure materials, can last several lifetimes in certain applications. Newer tubes in general aren't/won't be that way. Although some of the current production tubes have gotten a lot better.

I perfer the sound and reliability of tubes from the 50's and 60's. These tubes in general are 45-55 years old and of the tubes that have come thru my gear (all used, not new for the most part) only a couple showed signs of being at the end of their life cycle. I have signal tubes that were designed for a life expectancy of 10,000-20,000 hours of continuous use.


H9

Erik Tracy

Thanks guys....food for thought....

Is there some solemn ceremony when a cherished tube finally dims forever?

Maybe a party for a wake, or private grieving?

heiney9

The thing with tubes especially older tubes is they don't fail all that often. Not sure what your thought process is, but it's not like you are going to buy a piece of gear and every year spend money on new tubes. Now this could be true of some of the current production stock but then typically the cost of some of the newer tubes is a lot less.

Just as an example; you buy an amp that uses the popular EL34 power tubes. You can buy new production EL34's for let's say $60/pr. You can buy slightly used Mullard EL34's from the 60's for about $200-250/pr. The old Mullards are most likely going to last a very long time, but the new production EL34's might last 2 years. So you can see the trade off and the old Mullards will sound better too.

The above is just a general example.

Signal tubes I wouldn't worry about because they last forever or atleast a lot longer than a power tube.

H9

decal

Erik Tracy wrote: »

Thanks guys....food for thought....

Is there some solemn ceremony when a cherished tube finally dims forever?

Maybe a party for a wake, or private grieving?

Naw, just unceremoniously throw them in the garbage and continue on.

falconcry72

I'm a tube nube, so I can't really make definitive statements about quality, but, in my line of thinking, there's great solid gear, and there's great tubed gear; neither is inherently better.

Having said that, getting into tubes has added a completely new dimension to the audio hobby for me, and I love it. This is because one of my favorite parts of this hobby is the hunt: researching, learning, seeking, and scoring. Tubes add a new territory within which the hunt can exist.

heiney9

I too immensely enjoy the hunt and the research for tubes. And yes there is some great SS gear out there, but tubes in the mix with the best SS gear out there is simply sublime. Tubes Rule............and Tubes add Soul.

H9

inspiredsports

falconcry72 wrote: »

Yea they're consumables, like batteries.

There are tube testers that can measure different performance aspects of tubes.

Another similarity to wine, is that certain older tube vintages can be better than newer tubes.

I would use the anaology, "they are consumables, like light bulbs" instead of "batteries".

falconcry72

inspiredsports wrote: »

I would use the anaology, "they are consumables, like light bulbs" instead of "batteries".

Agreed.

zingo

Is it possible that a majority of vintage NOS tubes are of good quality because the bad ones didn't make it? They have either been tested and weeded out over the last 40 years, or they last because they are the best of the time and thus have a reputation for that? I'm not speaking poorly of vintage NOS tubes because they are great, but does age play a factor besides just, "made with better care, craftsmanship and especially better and more pure materials"?

Toolfan66

It's nice to poke my head in a thread talking about tubes and it's not all gibberish to me like it was over a year ago..

Tubes do rule!!!!!

mhardy6647

How consumable they are depends on the application (output tubes dissipate much more power - heat - from their plates than, say, a voltage amplifier like a 12AX7) and, especially, on the operating points used for the tube in the amplifier design. McIntosh famously ran its tubes, even its power output tubes, at moderate voltages and currents, and the tubes in vintage Mac amps (not to mention tuners and preamps) can last a long, long time.

Most of the small signal tubes in my vintage hardware (50 and more years old) are still fine, fine, fine.

Keeping the bias correct (on amps with adjustable bias - such as some so-called "fixed bias" :-) amps) helps the longevity of output tubes considerably.

Some modern designs really abuse tubes - there was a fairly modern (not current production, IIRC) preamp that used to just plow through its small signal tubes (maybe 6922s? memory is faulty...) because it ran 'em so hard.

Again, if memory serves... Western Electric made 300Bs to last 30,000 hours - because they really didn't want them failing left and right.

EDIT - 40,000 hours according to the modern "Western Electric" http://www.westernelectric.com/support/faq.html

heiney9

Old tubes are made better, with better materials, more pure materials and better craftsmanship. Plain and simple. That's not to say that some of the new crop of tubes aren't good quality, but I doubt they will last 40-50 years. Tubes are more of a commodity now than they were back in the day. What I mean by that is back n the day a tube was like a light bulb, it was needed. Today tubes are a bit esoteric and one has to choose to use tube gear. Therefore tubes being sort of a "boutique" product I think the end result is to make money not for utility. Many times when you manufacture a product for purely profit making reasons there are short cuts to maximize profits; it's Business 101. And the fact that most of them machinery, craftsman. processes and materials aren't readily available. I also believe not as much care is taken to produce them today. Did you ever see some of the footage of the old tube plants? You could eat off the floor and machinery in those places.

H9

mhardy6647

heiney9 wrote: »

Old tubes are made better, with better materials, more pure materials and better craftsmanship. Plain and simple...
H9

There is that.

reeltrouble1

I have a wonderful tubed Magnavox stereo radio purchased new in 1959, the original tube set is still being used. Recently the tuner dial quit working....so the fire bottles outlasted the mechanical dial, at least in this case.

RT1

[Deleted User]

I believe the Western Electric 300B tubes were used in the early transatlantic cable in relay amplifiers. In other words they were placed in water tight boxes along with the rest of the circuitry and dropped to the bottom of the Atlantic ocean. They had to be thoroughly tested and rugged, nobody was going to pull them up off of the bottom of the sea to replace a bad tube.

amulford

I think you are right. It was relatively low power and voltage, and those relays were engineered and made to last for YEARS in one of the harshest environments on the planet. I think they were actually built, cased and then epoxy filled to keep the salt water at bay, so no tube rolling for those puppies.

But again we come to the point of old school craftmanship and pride. They truly don't make them like they used to. Today the general school of thought is finite (and short) life expectancy to fuel consumption. QC standards are not the same, what matters is the numbers produced. Darn shame, really. sooner or later the supply will run out...

mhardy6647

Kenneth Swauger wrote: »

I believe the Western Electric 300B tubes were used in the early transatlantic cable in relay amplifiers. In other words they were placed in water tight boxes along with the rest of the circuitry and dropped to the bottom of the Atlantic ocean. They had to be thoroughly tested and rugged, nobody was going to pull them up off of the bottom of the sea to replace a bad tube.

I have heard that too. They were definitely used in the "long lines" overland... and back in the days when The Bell System was using 300Bs, those stations could be pretty darned remote.

steveinaz

I have a 1936-37 vinatge Philco console radio--all original tubes, and it works to this day.

mhardy6647

This ol' RCA 2A3 (which I procured used) is old enough to be my father...