tube upgrade for first sound

Has anyone been able to improve on the stock tubes in the First Sound preamps? I was thinking about trying the Russian 6H23. Any thoughts? thanks

84audio12-22-2003 3:27am

1markr Details Discussions Posts This discussion Message User 594 posts 04-17-2004 at 04:02am Copy Comment URL Report Comment Edit Delete Amperex 7308s (USN-CEP, or JANs, or PQs).