I'm going to try the Penta Labs 12AX7 in V1 of my Mr. Hector. Any comments about RUBY 12AX7AC5 tubes for example in V2 and V3
My sockets goes like this V1 - first stage in preamp, V2 - second stage , only for Gain channel, V3 - stage 3 of the preamp, V4 - inverter