Quote Originally Posted by tunghaichuan
That should be taken with a grain of salt. The EL84 by design is a high gain tube and power tubes in general tend not to be microphonic like preamp tubes. If they are using the Sovtek EL84M, that is the Russian mil-spec version of their EL84.
I have two Sovtek EL84Ms which was in my Blackheart when I had Tung-Sols in it too. My idea was to make the amp as transparent as it can be for the pedals and that seemed to work.