Tung Sol NOS Black Plate 6550 – Temperature

I just replace my ARC Ref 6’s stock Sovtek 6550 to a Tung Sol NOS Black Plate 6550 (3 getters) yesterday.  Although the difference between these tubes’ sound quality is not huge, in my opinion Tung Sol NOS 6550 seem to be better than stock Sovtek 6550.   Tun Sol NOS has better resolution, better solid bass, better sound stage…. But one thing I’m quite sure, Tung Sol NOS 6550’s temperature seem to be higher than Sovtek 6550, Tung Sol NOS is much hotter. Does any Tung Sol NOS 6550 user also have this experience? Thx.