Pass Labs , officially known as Pass Laboratories, Inc., is a prominent high-end audio company founded in 1991 by renowned audio engineer Nelson Pass. Based in Auburn, California, Pass Labs is celebrated for its innovative and meticulously crafted amplifiers, preamplifiers, and speakers. The company is particularly known for its pioneering work in Class A amplifier design. Nelson Pass, the founder, is a legendary figure in the audio industry, known for his contributions to amplifier design and his commitment to the DIY audio community. Pass Labs continues to innovate and expand its product offerings, maintaining a reputation as one of the leading brands in the high-end audio market