Dennis Had Inspire Amps

[david45]

Originally Posted by nhparrot

Output Tube - Rectifier Tube
6L6, 5881, or KT66 - 5AR4, 5U4, or 274B
6V6 - 5Y3, or 6106
6V6GT - 5U4, 274B, 5Y3, or 6106
EL34, 6CA7, or KT77 - 5AR4, 5U4, or 274B
6550, KT88, KT90, KT120, or KT150 - 5AR4, 5U4, or 274B

Input Tubes
6BX7 - Has a deeper sound stage with more weight in the lower mids.
6SN7 - Has more gain than the 6BX7 with lower midrange heft
6SL7 - Has more gain than the 6SN7 and sparkle in the top end

For my 6L6 Firebottle (SEP) built in January 2015 output was tested by Dennis as:
Output Tube - Power
6L6, 5881, or KT66 - 8 to 10 watts
6V6 - 6 to 8 watts
EL34, 6CA7, or KT77 - 8 to 10 watts
6550, KT88, KT90, KT120, or KT150 - 9 to 14 watts

6BX7GT as input tube perhaps? Should I give it a try and order some?