Tip of the Week: swapping preamp tubes
Mon, 06/13/2011 - 10:20
A recent question on the forum has inspired this tip. When substituting preamp tubes in an amp to help with volume, tone, and (especially) feedback, remember that it is the change in gain that really makes the difference. Sonic differences between say, various brands of new and vintage 12AU7s can be subtle, especially for beginning players, but subbing any 12AU7 in place of a 12AX7 will really make a big change. So don't worry about buying the "best" tube, just grab a handful and start experimenting!
Skip Simmons
I have just bought a mojo switch from lone wolf to reduce and possibly eliminate feedback on my fender pr 266 ‘evil twin’ and Selmer truvoice treble and bass fifty 1964 vintage head.
I took the tubes out of the Selmer yesterday to see which type there are and snapped the plastic bit at the bottom of the tube near the pins and it now sounds hissy, is that due to the broken one ? I have ordered a pair of groove tube valves to replace if I need to.