Conrad-Johnson Premier Seven preamplifier
Whenever an audio high-ender thinks about tubes, he usually thinks about Audio Research. This is only natural, because Audio Research Corporation was almost single-handedly responsible for saving tubes from oblivion in the early '70s when everyone else switched to solid-state. But ARC was soon joined in its heroic endeavor by an upstart company called Conrad-Johnson, which entered the fray in 1977 with its PV-1 preamp, priced at an affordable (even then) $500.