EL-34 power tubes, along with their smaller EL-84 cousins, brought British amp tones to the fore in the ’60s and ’70s. Famously featured in Marshall amps, EL-34 “valves” (as the Brits call them) offer an assertive tone with a midrange emphasis; since midrange is where guitar tones live in the frequency spectrum, amps with these tubes tend to sound louder than amps with similar wattage ratings but different tube configurations.
