While there have been countless developments in the science of signal amplification over the decades, the original vacuum tube is still the best in the eyes of many. Tubes or valves are remarkably inefficient and inconsistent devices in many ways, but it is this variation and character that makes them ever sought after by the insatiable tone-thirsty guitarist. Whether a 6V6 breaking up in a vintage combo amp, a 12AX7 adding sizzle to a hybrid or a big bottle EL34 or 6L6 bringing dynamic roar to a 100 Watt head, the humble tube is still the cornerstone of electric guitar tone.