EI 12AX7s in a Soldano

I tried several 12AX7s (including EI) in the first tube socket in my Soldano. I liked the Sovtek LPS the best. Punchy and clear. But they can't make me play like you, my man!!!

 

I tried several in my Engl and all but one were microphonic and the one that DID work had almost no gain, as if it were a 12AT7. I prefer NOS or a mixture of JJ with sovtek 12AX7wb or EHs.

 

Sounds like your particular EIs had a problem. Random samples of ANY brand of tube can be microphonic or have low gain...you must buy them from a dealer who tests them and ships only the ones that pass.

Note that the early production EIs are famous for being microphonic but the more recent EI Elite tubes are much improved. I test tubes by the 100s so I've got some pretty good data.

New production tubes with the lowest microphonics are EHs, Chinese R9s and JJs. Of these, JJs have horribly inconsistent gain indicating very poor quality control and lack of screening/testing at the factory. The other 2 are VERY consistent.

Tone is another matter. There's no product that everyone loves.

 

Ariel Pozzo ...............

With a 60% reject and failure rate from the factory, make sure these are well tested by a known good vendor.

These are the brightest 12AX7 family tubes around, so in your amp they may be too bright.

By the way .... Mike at KCA has great versions of this tube. There is one vendor out there that does not, and is particularly awful, so beware.