When it comes to both safety and accuracy, the Brownie blows any variac out of the water. For starters, its in-rush current protection absolutely limits AC input, while its output only reduces voltage, preventing you from accidentally blowing up your amp. A Hi/Lo switch lets you adjust the input voltage rescaling to ensure efficient and accurate operation, and a 5-way selector knob lets you choose from 4%, 8%, 12%, or 16% attenuation plus a bypass setting so you can A/B the result. Top it off with a backlit LCD voltmeter, and optimizing your small tube amp's input voltage is a piece of cake.