Cary Audio Design CAD-300SEI is an exotic vacuum tube audio amplifier with incredible reliability and enjoyment. The device is designed to provide the most realistic sound reproduction and is ideal for a "high-end" home audio system. It operates in a Class A single-ended mode utilizing fixed negative grid voltage on the 300B triode output tube. The preamplifier section utilizes a 6SN7 dual triode tube, one triode section for the left channel and the other for the right channel.