Tube Amp Doctor tad black plate KT-88

I don't know,

I'll just chime in that when I changed from 6550's to KT88's, I definitely preferred the KT88's, even though the 6550's sounded darn good.

I can only comment on how this type tested versus other current production KT-88s. Recently I purchased large quantities, at least for me, of new production power tubes from an estate in California. Amon the KT-88s were TADs, reissue Gold Lions and Sovteks. All of these were factory matched and the only tubes which were actually matched to my satisfaction were the TADs. Both the Gold Lion and Sovtek tubes were fairly inconsistent in their testing. This may just be a flute or it may mean the TAD does a better job in selecting and matching their tubes. Thought you might find this interesting although I cant comment as to the sonics vs other KT88s.