C-rated – Like vitamin C, this is a good thing. The latest iteration of the Pass Labs HPA-1 headphone amplifier gains the 'c' suffix for a new power supply designed by the team's low-level signal wizard Wayne Coburn who is also responsible for all of the brand's preamplifiers. According to a source at Pass Labs, the new power circuit is a lot quieter and has improved the design's performance enough to warrant a new model designation.
