I have direct experience with almost all the current production EL34 tubes. Some are more than OK; many are highly disappointing, but maybe that's because I'm old enough to have been buying new Siemens, Telefunken, Mullard EL34s in the late 1960s through 1970s, for $6 - $20 per tube. So what do I use now?
The worst-kept open secret in EL34 is the big stash of Siemens EL34 that Mesa Boogie bought up in the waning years of German production. They then ran everything through their custom-designed tube tester before sale, dispensing with any bad ones (not many!). I use these.
You can order them directly off the "Parts & Accessories" store off the main mesaboogie site. The tube you want is the "EL-34 STR450" also parenthetically labelled Siemens NOS. Right now they cost $180 per matched pair. This is an objective EL34 with solid bass, extended top end and midrange magic tone without gumming up the presentation with molasses and honey. In the right amp it has the burstiness and speed of a KT88 without the telltale KT grit in push-pull.
If you have a rolled off speaker and want to give it a little top end life, the Preferred Series EL34 at The TubeStore site is robust, open and comparatively objective except for the somewhat hot (but clean) top end. It seems reliable too. The JJ E34L is musical and EL34-romantic, but keep spares (and spare amp fuses) around.
But if you want to bypass all these Russian and Chinese power tube anomalies, grab a quad of the Mesa EL-34 STR450 Siemens tubes from the late 70s into the mid-80s and put your feet up. They are long-lasting and will make your EL34 amp sound better than you thought possible. Fortunately for tube hifi, guitar players are cheap, so the Mesa Siemens stash slow to get depleted pushing 40 years.
My custom Williamson monoblocks erupt and bloom with them, bettering a lot of vastly more expensive amps.
Phil
The worst-kept open secret in EL34 is the big stash of Siemens EL34 that Mesa Boogie bought up in the waning years of German production. They then ran everything through their custom-designed tube tester before sale, dispensing with any bad ones (not many!). I use these.
You can order them directly off the "Parts & Accessories" store off the main mesaboogie site. The tube you want is the "EL-34 STR450" also parenthetically labelled Siemens NOS. Right now they cost $180 per matched pair. This is an objective EL34 with solid bass, extended top end and midrange magic tone without gumming up the presentation with molasses and honey. In the right amp it has the burstiness and speed of a KT88 without the telltale KT grit in push-pull.
If you have a rolled off speaker and want to give it a little top end life, the Preferred Series EL34 at The TubeStore site is robust, open and comparatively objective except for the somewhat hot (but clean) top end. It seems reliable too. The JJ E34L is musical and EL34-romantic, but keep spares (and spare amp fuses) around.
But if you want to bypass all these Russian and Chinese power tube anomalies, grab a quad of the Mesa EL-34 STR450 Siemens tubes from the late 70s into the mid-80s and put your feet up. They are long-lasting and will make your EL34 amp sound better than you thought possible. Fortunately for tube hifi, guitar players are cheap, so the Mesa Siemens stash slow to get depleted pushing 40 years.
My custom Williamson monoblocks erupt and bloom with them, bettering a lot of vastly more expensive amps.
Phil