RCA and Sylvania
first introduced the 12AX7 to the world in the late 1940’s. Today, it is by far the most common preamp
tube used for electric guitar amplification and there is an almost overwhelming
supply of current production options to choose from. The purpose of this comparison is simply to
provide guitar players with a frame of reference to help in finding the best
current production 12AX7 for their needs.
Also included in this comparison are direct substitutes for
the 12AX7 including: ECC83, ECC803, 7025
and 5751.
