Building a Silvertone 1484. Can I use a 12AX7 for the PI? Schematic calls for a 6CG7. Maybe there’s a way to make it work.
use a 12au7, be mindful of the pinout differences I'm guessing it's a long tail pair, you can pop in values here: https://www.ampbooks.com/mobile/amplifier-calculators/long-tailed-pair/
I’ve basically built this out of a 2204 clone. PI and power section is still a 2204. Preamp is a 1484 without the second channel. Sounds very clear and crisp so far! Very fender like. If I use a 12AX7 instead of a 12AU7 will the PI generate way too much gain? Also: I want more gain. Should I add the second channel like on the original, and jump the inputs? Or should I add another gain stage? I’m assuming blackface bassman mods could work with this amp?
ahhhh gotcha i just mentioned the 12au7 because it's a similar tube to the 6cg7. in a cathodyne itself you're not getting much gain regardless of what tube is in there. 12au7 is theoretically capable of more current drive than 12ax7. where the cathodyne shines is that it uses a single triode so it frees up the other half for another gain stage i prefer the long tail pair myself, but in the one cathodyne phase inverter amp i have i can tell you that the "paulc mod" often done on princetons is a must
This 1484 circuit is loud as hell! Way louder than the Dookie Mod curcuit that i had in there. I increased the gain a bit by lowering the cathode resistor in the second stage. Such a unique overdrive sound.
if you have issues with "overdrive swirl" from the phase inverter, look into the "paulc mod" that's often done to the cathodyne in fender princetons. some folks seem to like that sound, i can't effing stand it
