2. tech-talk
  3. 1146161092

Tube Test Results

I've read descriptions of tubes for sale here claiming that claim the tubes for sale "Good" or "Excellent" on their teting machines. What does this mean?

If a tube is not "Excellent" does that mean that their is not as much life left but, sound quality is not affected or, tube life is deteriorating and sound is too.

I guess my ultimate question is, do tubes burn out like a light bulb - running strong until the filament burns up or, do they die like a battery - less and less energy over time?

Talking about specifically 6SN7GTs as an example - if that matters.

thanx
pawlowski6132

Showing 4 responses by pawlowski6132

pawlowski6132 OP
592 posts
 
Here's a follow up question; more specific I guess. I see lots of tubes with tester measurements such as, "1700/1700." Followed by a comment that 2500 is 100% or "65/65 where 140 is new."

Can I draw any real inferences from these? For example, if a 6SN7, assume, lasts 5000 hours, can I asume that a tube meauring 70/70 will only last 2500 hours??

Why are there two numbers?

thanx guys
pawlowski6132 OP
592 posts
 
John do you mean two electroes to test: the cathode and the anode, withthe plate being the third (i.e. triode?) If so, I guess that makes sense then. But, what do the numbers represent?
pawlowski6132 OP
592 posts
 
Jburidan, thanx. That really helps.

Say I'm using a 6SN7 in the driver or input section of an integrated amp. Will it be obvious when the tube dies? Will it blow up? Will the volume just drop? Will it get staticky??

thanx much
pawlowski6132 OP
592 posts
 
Thanx. So, sorta like me the next morning after a night out.
More to discover