I own a EL84 powered amp (Blackstar HT-20mkII)... and well, lowering the volume/breakup point would be great for my situation-
(playing in livingrooms, with other acoustic instruments).
Please reply guys, if you know anything about this tube!!
Both tubes have a limiting value of 300 volts, if the AC30 or Boogie DC3 takes regular JJ EL84's, it will take the JJ EL844 just as good towards voltage.
If you are after lower volume the JJ EL844 will deliver, they should break up about 25% earlier than the EL84 as well, so if that what you're after, the EL844 is the one to get.
If you're expecting to sound like the 84 but a bit lower volume I think that's probably where most reviews go wrong. It's a different profile. Early breakup, quieter and a slightly different tone. Supposedly it's closer to the full EL84 than if you activate a triode/pentode power saving method.