Before the late 1950s, every amplifier available to musicians had a power supply that used rectifier tubes. That changed with the invention of the transistor and the development of solid-state and hybrid amps, but these tubes live on in vintage, boutique and all-tube amps. Today, there are plenty of casual and professional musicians who continue to prefer the unmistakeable classic character that comes with the traditional rectifier tube.
Unlike preamp and power tubes, rectifier tubes don't actually process the audio signal directly. Instead, their job is to convert AC power from the wall outlet into the DC current that your amp's other tubes run on. When it comes to your sound, this means that the effect of changing rectifier tubes is a bit more nuanced than it is with the other two types. The characteristics of power and preamp tubes actually change—in some cases, significantly—at different voltages. As a result, your choice between a 350-volt and a 400-volt rectifier tube, for example, will actually alter the performance of the other tubes. Read More >