AmpRX Eurovolt Voltage Optimizer, Variable Voltage Supply, The right supply voltage is crucial for the optimal performance of a tube amplifier, Dynamics, sound, response and feel change at different voltage levels and from stage to stage, Select and maintain the specific voltage required for the amplifier's fundamental tone, Voltage reduction can be selected from a range of safe reduction levels to discover other tonal options, Backlit LC display for real-time indication of voltage and current or for diagnostic purposes, Quiet, cool operation, Specially wound 2.5-amp transformer for use with valve amplifiers, Delivers up to 440 watts at 240 volts (please check the manufacturer's nameplate on the back of the chassis for the required input power), Coarse reduction: Off, -10V, -20V, -30V, Fine reduction: Bypass, 2%, 4%, 6%, 8%, Connections: 1 IECC male IEC socket, 2 female IECC IEC sockets, Handmade in Holland