Having used Fender amps my whole adult life, and owning at one time or another almost every iteration of Blackface and some Tweeds, I thought I had it narrowed down to one tube (actually a pair): the 6v6. I've had a Swart AST since summer, and all that has been said about this amp is true. It is (to me) the be all and end all of old school 6v6 tone. Loaded with NOS tubes, it is May 1953 in a smoky juke joint somewhere, the valves are glowing, the pipes are sweating, the sound is thick....Oh wait, it's really my smoke-free basement and I'm gagging on my own hyperbole. (Great amp, nonetheless). Enter the Goodsell Super 17 I had never really considered the EL84 tube for some reason. It doesn't sound American, it's only for high gain, it's fragile and temperamental, it looks like a dang preamp tube, etc. Boy, was I wrong. I received my Super 17 about 2 weeks ago, and have come to embrace the smallest of power tubes, in no small part because of this great amp. With its simple circuitry and little to impede the signal, it sounds like you're plugging right into the tubes which are in turn hooked up directly to the speaker. Now I know enough about electronics to know there must be a resistor, or a capacitor, or some kind of doodad in there somewhere, but it doesn't sound like it. My initial worry was that the sound would lack depth or be spikey or sound all English and everything, but that is not the case. It is a full spectrum sound, with enough bass for jazz chord melody work on one end, and all that beautiful chimey stuff on the other end. In the final analysis, I have come around to the EL84 tube. It seems the most sensitive to playing nuance of all others I've tried. And, of course, when you get the gain up, it is a great ride. I would like to mention that Richard Goodsell is the real deal. A stand-up guy who seems to know about all there is to know about this stuff, and is passionate in his pursuit of the zeitgeist of that old tube sound. Did I mention it has reverb?