I experienced the same thing when I first switched power tubes in my Jolida a while back...new KT120s. Freaked me out but it stopped, so I can only assume the tubes have some external coating or an adhesive on the tube base or something, as it happened again when I stuck a new pair of 88s in the thing. I now simply call it the "new tube smell." It went away after the tubes were in use for a day or 2 and never came back. I bias according to the amp specs, not the tube type recommendations and that seems to work for my amp as it sounds fine and the 120s are holding up well.
Tung sol 6550 tube smell??
I bought new tung sol 6550 tubes for my audio research vs110. The original tubes for that amp were sventlana 6550 tubes that were great and i never noticed a smell from the amp. When i put in the tung sol reissues, i biased the amp at 55ma to save some tube life. When i had the sventlanas, they were at the recommended 65ma. So i dont know why i have a pretty strong burning smell comming from the tung sols. Is this because the tubes are new, or mabey they cant handle the bias? im very concerned, i hope my amp dont blow up or the tubes. Thanks, rob