Why do NOS Tubes sound better than new tubes?

Is manufacturing really that backwards in todays techno world? What is the real reason that todays tubes cannot equal the tubes of yesteryear?

tubed108-26-2011 2:39pm

4est Details Discussions Posts This discussion Message User 507 posts 08-26-2011 at 07:15pm Copy Comment URL Report Comment Edit Delete New tubes are a niche market, whereas years ago they were required by the most demanding applications.
marakanetz Details Discussions Posts This discussion Message User 5,473 posts 08-26-2011 at 07:23pm Copy Comment URL Report Comment Edit Delete Back then everything depended on the tube quality and stability whereas now there's an improvement of circuit engineering.
hifihvn Details Discussions Posts This discussion Message User 943 posts 08-26-2011 at 07:32pm Copy Comment URL Report Comment Edit Delete This was posted recently. You could see in the old videos how much they tried for quality. [http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1314237934&openusid&zzHifihvn&4&&]