12AU7 is a high-gain tube very often used in power amplifiers as the driving one. It's also dual-triode that can be used in differential inverting connection just like OPAmp.
6922 is also dual triode has a lower gain than 12AU7 but used for the same purposes where large isn't neccessary i.e. in preamps.
Could be the other way arround but I guess that mainly 6922 is used in preamplifiers
6922 is also dual triode has a lower gain than 12AU7 but used for the same purposes where large isn't neccessary i.e. in preamps.
Could be the other way arround but I guess that mainly 6922 is used in preamplifiers