Stick to a direct coupled solid state amp on Tektons. The only Tube amps I have ever heard that I could live with, I can't afford. Audio research REF 150, VTL MB 185, 450's, Manley Snappers, and some huge McIntosh tube monos that cost 22 grand . Go FET's on the solid state if you can. You can put a tube preamp on the solid state amp if you want to sweeten the sound. Word on the street is PASS LABS is the best amp to put on Tektons.