Vintage Component Spotlight: Carbon Composition Resistors

Carbon composition resistors are those brown cylindrical resistors that you’ll see in most amps made before 1970. All resistors produce Johnson (thermal) noise, a byproduct of the fact that resistors dissipate heat. However, depending in their material composition and shape, resistors may produce other types of noise as well. Carbon composition resistors produce the most noise. But is this really a bad thing? Yes and no.