With a single gain stage, the Reference 6SE is a fully-balanced, Class-A design with zero feedback. In addition to six long-life 6H30 tubes in the gain stage, the enormous and highly-regulated power supply has another 6H30 with a 6550 providing vacuum-tube regulation. The Reference 6SE replaces the Reference 6 and offers the highest performance ever available in a single-chassis preamplifier. Benefitting from the development that went into the Reference 160-series amplifiers, and the latest Reference 750SEL, the 6SE incorporates a myriad of new parts that have been judiciously incorporated into its design.