We've
compared these to all of the classic European EL84’s, U.S. 6BQ5’s and the
current Russian EL84’s. The JJ’s seem to fall right between the Philips 6BQ5’s and
the Mullard EL84’s. Very smooth with a sweet chime, a very defined mid and
tight punchy low end. Overall, one of the best EL84’s we've ever heard. Mike Zaite of Dr. Z amps gave the following
review of the JJ EL84 "The JJ tubes are long lasting, strong and give
increased power output. This tube excels in headroom and balls. Great rock
tone, punchy, with a strong attack." The JJ EL84's were reviewed by Dick
Olsher on enjoythemusic.com in a review of the Manley Labs Stingray amp where
they stated the following. "The end result was a definite WOW! The sound
of the Stingray was transformed into a darker and richer sonic life form."
After
a 24 hour burn in all power tubes are tested for noise and matched at multiple
operating points for plate current (± one milliamp) and transconductance.