I need some tubes tested. Anybody here do that ?

I test tubes. Nothing pre war though, My B&K tester doesn't have 4 and 6 pin sockets as it was built in the era of color TV. It will test Nuvistors as well.
 
Most guitar shops have a tube tester for the more common tube types. The one near me let me do my own tube testing on their tester.
Damn good idea. Never thought of that. I do not know if they do it around here but could damn sure ask.
Thanks.
 
I test tubes. Nothing pre war though, My B&K tester doesn't have 4 and 6 pin sockets as it was built in the era of color TV. It will test Nuvistors as well.
These would not be pre war. These would be Two. 12AT7's, One. 12AX7 and and Three. 5751's . They are in my conrad johnson PV6 preamp.
 
These would not be pre war. These would be Two. 12AT7's, One. 12AX7 and and Three. 5751's . They are in my conrad johnson PV6 preamp.
Funny, the 12AX7 and 12AT7 tubes are used consistently in guitar amps. The 5751 is a drop-in replacement for a 12AX7. The 5751 was designed as a "ruggedized" high mu, dual triode tube with similar specifications as a 12AX7. However, with 30% reduced gain, the 5751 is a fantastic way to reduce the distortion and add harmonic tone to an amp.
 
Have a few Conrad Johnson here that use these tubes in the preamps
 
Yep, paperwork says this. I think that is due to what you are talking about with the reduced gain...20221113_151614.jpg
 
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Don't discriminate against the indiscriminate substitution of your tubes... That needs a HUH!
The 5751 is wired the same as the 12AX7, the 12AT7 is not wired the same as a 12AX7, those two tubes are non-compatible.
 
That is beginning to sound kinda like a Herbert Spencer quote.
"There is a principle which is bar against all information, which is proof against all arguments and which cannot fail to keep a man in everlasting ignorance that principle is contempt prior to investigation." Bet you I get a HUH on that one!
 
That is beginning to sound kinda like a Herbert Spencer quote.
"There is a principle which is bar against all information, which is proof against all arguments and which cannot fail to keep a man in everlasting ignorance that principle is contempt prior to investigation." Bet you I get a HUH on that one!
Awesome quote, I like it. Think it applies to many of today's issues.
 
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