12bh7 TUBES

Hi,
I have 12bh7 tubes in my power amp,can I change with a 12au7 are they the same?

yogiboy06-03-2009 9:11pm

mofimadness Details Discussions Posts This discussion Message User 4,933 posts 06-03-2009 at 10:12pm Copy Comment URL Report Comment Edit Delete It depends on the circuit. You can't make a "blanket" statement that "ANY" 12BH7 can be subbed for a 12AU7 and vice versa...
gmuffley Details Discussions Posts This discussion Message User 132 posts 06-03-2009 at 11:16pm Copy Comment URL Report Comment Edit Delete The 12BH7 tube draws twice the filament current of a 12AU7, so that can be an issue if the filament supply has marginal current capability.
jax2 Details Discussions Posts This discussion Message User 3,031 posts 06-04-2009 at 05:19am Copy Comment URL Report Comment Edit Delete Per above, ask the manufacturer of the amp. They are not identical.
yogiboy OP Details Discussions Posts This discussion Message User 5,464 posts 06-04-2009 at 07:36am Copy Comment URL Report Comment Edit Delete Thanks for the info,I got in touch with manufacturer and said I can use but will not last as long the 12bh7 is a stronger tube.