old tubes, what to do?

[djQUAN]

I found at home a box full of old tubes from the 60's to 70's era.

probably about 30 of them. mostly are still boxed and unused but the cardboards are deteriorating.

some 6CB6, 6AL5, 6AX4, 6K6 and many more others. I'm thinking about tinkering with a tube preamp?

well, this is going to be my first attempt with something "tubed"

[djQUAN]

anyone got schematics for me to start with?

[ErikdeBest]

Hi

First of all, read this:
Safety Practices, General and Ultra-High Voltage

and

Safety Practices, General and Ultra-High Voltage

After you've done that, I would recommend you start with identifying the tubes you've got. All tubes can be used for audio (according to sh3mat1c), but some are better than others. A good tool is de tube database from duncanamps.

http://tdsl.duncanamps.com/tubesearch.php

Or type the code of the tube in google or in the search function from this forum, together with "amplifier", "audio", "pre amplifier" and see what you get.

[djQUAN]

oooh, interesting. thanks for the links.

*starts with the reading*

although one question,. do older tubes have shorter working life than newer tubes? (I mean older by date or period of manufacture, not by how long they were used)

[djQUAN]

I have narrowed down my tubes to 6 candidates.......


6AL5, 6BQ7, 6AU6, 12AU7, 6CB6, 6X8 -these I have atleast two or three.

any experienced ones have any suggestions for a tube preamp (line in to line out, maybe a tube buffer?)?

[djQUAN]

I'm thinking this one.........

going to build a 12au7 pre what do you think?

[rcavictim]

Originally posted by djQUAN
oooh, interesting. thanks for the links.

*starts with the reading*

although one question,. do older tubes have shorter working life than newer tubes? (I mean older by date or period of manufacture, not by how long they were used)

N.O.S. (new old stock) vacuum tubes from the first time vacuum tubes ruled are often of superior quality to those manufactured today and can actually last longer than modern examples of trying to manufacture vacuum tubes.

[djQUAN]

Originally posted by rcavictim



N.O.S. (new old stock) vacuum tubes from the first time vacuum tubes ruled are often of superior quality to those manufactured today and can actually last longer than modern examples of trying to manufacture vacuum tubes.

hmmm. that's a good thing in my case.

in my case, these are very old ones. but I don't know where to get replacements after these things stop working. worry about that next time.

[Mr. Triatic]

well, finding NOs tubes or even new ones of those types you have got is rather easy today..
-But, NOS tubes are like the worlds oil-resources, someday it's just gonna end 8-(

[djQUAN]

But, NOS tubes are like the worlds oil-resources, someday it's just gonna end

so buy enough to last you a lifetime then you won't have to look for them when you need some.