12AX7/ECC83:
12AX7A, 12AX7WA, 12AX7WA/7025
(SOVTEK),
12AX7WXT (SOVTEK), E83CC, ECC803, 5751, 6681,
7025, 7729, CV492, CV8156
6N6P
(6H6P, cyrillic):
no substitution; available factory-direct only
from LAMM
NOTE:
we recommend replacing
6N6P tube about once a year
to maintain the best
performance of the amp
6AK5:
6AK5W, 5591, 6096, 6968, 5654,
WE403B, EF95, 6F32
(second choice:) 6AU6, 6AU6A, 6136, 7543,
8425A, EF94
5651A:
5651
6C33C-B:
6C33C