2. amps-preamps
  3. 192573-139717

DON:T WAIT! Replace Those Old Power Tubes!

For several years I've cobbled together the required quad of 6L6GC power tubes for my Raven Audio Integrated amp. I say 'cobbled' because out of two sets I culled four which would perform what I perceived as reasonably decent sounding. Being on the last best four I feared one more failing tube would put me out of the music. So, I ordered another quad from Raven Dave (Thomson). At first I thought to just saved them for an emergency but on a whim I decided to just put all the Chinese New Old Stock (NOS) in place. APPARENTLY, and obviously, my smorgasbord set in place previously had various quirks including but not limited to: hum, occasional buzzing, and a bloated`slow tone. My wife immediately stated: I don't hear anything in the background. Indeed there isn't anything but dead silence. NOS tubes are always a "Russian roulette" deal but their unique and amazing "real-ness" is worth the gamble. (IMO) So if you have been waiting until you absolutely have to, DON'T WAIT any longer. The improvement is profound. These tubes are as old as I am! Only difference is I've not been in a box traveling around the world for over 60 years! 

allears4u
oddiofyl's avatar
oddiofyl
3,921 posts
 

I agree with Elliott. I test all tubes before they go in my gear for shorts and Gm.   Even then it's no guarantee.  

I bought a tester and few years ago when I started playing with rectifiers and DHT tubes .  It wasn't cheap but it saved me from putting what was no question a bad  NOS tube in my amp.   I bought 6 of the same tube, same JAN box, lot # etc but there was a bad one in the mix.   

My failed tube count over the past 25 years is low but I wish I had a tester years ago.   It only makes sense if a number of components are tube, but it is valuable when you have a problem.  

harleyujoe's avatar
harleyujoe
52 posts
 

May I ask what tube testers you own and how accurate are they...

I know when Dave Thomson of Raven Audio sends me tubes they 

all are marked with the test all done on them...

All my tubes come from Dave for my Amp ..

ashoka
99 posts
 

Poetic, hard to understand. Not for everyone

oddiofyl's avatar
oddiofyl
3,921 posts
 

I have a Hickok 800 , it seems pretty accurate with a few tubes that I have that were matched on a modern Amplitrex tester.  

Sure it's great to know how strong a tube is but it is far more important to check for shorts and gas.  

I was lucky, the one I picked up looks like it was in a museum.   It was serviced a few years ago and gives consistent readings.   Not usually the case with old testers.  

invalid
1,207 posts
 

@oddiofyl  that's right, testers are great for weeding out shorted or bad tubes, not so much for tube life or even for matching. Testers don't test tubes at real world operating voltage and current.

More to discover