Looking at the Russian made Mullard 12AX7 tubes on the Tube Depot web site, they offer options of: "matched and balanced" , " low noise and microphonics" and " high gain".
In my Jolida phono preamp, I do not beleive that gain will be a problem and the Mullards have relatively high gain anyway per the articles I've read... but I am wondering if I should spring the the surcharges for both the " balanced and matched and the low noise?
Forgive my ignorance, I'm still a tube novice...
thanks for sharing your thoughts and expertise.
Jim