This is not the answer you have asked for, but it may be of some help:
Good 6SN7s are MUCH more important than cones in a Capitole amp. I prefer Sylvania JAN 6SN7WGTA. Others like NOS TungSol or the european equivalent tubes.
It also pays to roll the output tubes. I prefer JJ E34L and Gold Lion KT-88 from current-production tubes. They do make a huge difference.
IME Herbie's Isocups do a great work of isolating tube amps from external vibrations (better than BDR cones IMS).
Enjoy your amp
Good 6SN7s are MUCH more important than cones in a Capitole amp. I prefer Sylvania JAN 6SN7WGTA. Others like NOS TungSol or the european equivalent tubes.
It also pays to roll the output tubes. I prefer JJ E34L and Gold Lion KT-88 from current-production tubes. They do make a huge difference.
IME Herbie's Isocups do a great work of isolating tube amps from external vibrations (better than BDR cones IMS).
Enjoy your amp