Putting vintage tubes in the power supply of pre

Some of the greatest sonic benefits in this hobby are achieved via power supply mods. ie: (http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1238465914&read&keyw&zzmullard+5ar4) That refers to the improvements in a power amp, in which the output stage's gain is realized as current(read the post following his rectifier replacement). Your pre's gain stages are all voltage, but the voltage that's modulated(YES- that IS the correct word) by the signal, and conveyed to the next stage, all comes from the wall outlet, via the power supply. The tubes you choose to use in your PS can have a dramatic effect on your presentation.

Just a suggestion: try a NOS Mullard 5AR4/GZ34 from the Blackburn plant, in the rectifier slot first, and listen for improvements. Then find a NOS TungSol 6SL7GT/VT229 Round Plate(from the 40's). There are a lot of good NOS 6V6 power tubes that will each give you a different flavor in your presentation. ie: If you want a bit more warmth; you might try a pair of Brimars. For a cleaner, more detailed sound; Sylvania or Ken-Rad. RCAs will be somewhere in between. Have fun, and enjoy your music.