Stax SRA-7S integrated amp for earspeakers.To sell a very rare tube preamp and amplifier for electrostatic headphones. Fully restored.Replaced the resistors of the cap and potentiometer. Very clean and sweet sound with beautiful highs and bass. The left output is connected to 580V for Pro bias headphones. The right output is connected for Normal bias headphones. Power 100-117V. There are small scratches and dents on the top right corner of the photo. The phono input is in excellent working order.