• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

New Production EL34/6CA7/KT77 - Distortion measurements & curve tracer

I have used the JJ KT77. It works good, and "sounds" good.
If you connect a wire from pin 1 to pin 8, you can use the EL34 and the 6CA7, in the KT77 socket.
Plug and Play . . . instead of Plug and Pray.

Are you planning on using the tubes at, or very near, to their maximum specifications.
Then pay close attention to things like Maximum Rg resistance versus fixed bias or self bias;
and the restrictions on the Total dissipation of the plate + screen;
not the simple sum of plate max dissipation spec, and screen max dissipation spec (for some tubes the Total dissipation max, is less than the simple sum of the individual dissipation specs).

Yes, those tubes qualify for good Hi Fi, depending on how you use them.
Tell us your amplifier design details.
A blindfolded Archer hardly ever hits the target.
 
Marantz Model 9's. The EH 6CA7's sound great in ultra linear but lacking just a tad in Triode mode in the midrange. I purchased these for their reputation of good sound in Marantz's and their reputation for reliability.

I know Telefunken was the best for these back in the day and were the lowest distortion EL34.
 
This is mostly an old production comparison I have attached. Not sure about new production and these measurements were taken 20 or so years ago. Telefunken was the best EL34 type, JJ EL34 not bad but I am scared of their reliability.

Not sure how faithful the newer KT77's are as the original Genalax was great.
 

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