Audio Research VT100

The VT100 is an all-tube, balanced stereo power amplifier that draws upon the advanced technology of the flagship Reference Series models. Rated at 100 watts continuous output per channel, the VT100 is a Class AB, differential circuit design using two matched pair of 6550 output tubes in each channel, along with four 6922 twin triodes per channel for input and driver stages. A fully regulated, 540-joule power supply is distributed between two separate, isolated output circuit boards for short signal paths and true "dual mono" operation back to the massive main power transformer. Constant-current sources in the input stage help maintain stable drive characteristics and differential balance under the dynamic conditions of music reproduction.

Ultralinear output transformers and partial cathode coupling to the output terminals give the VT100 higher efficiency and lower output impedance than conventional designs for better drive into a wide variety of loudspeaker loads. Inputs include both single ended and balanced. Output terminals are custom-machined, heavy duty, gold-over-brass posts. A spacious chassis helps maintain conservative operating temperatures.