Cambridge Audio started in a borrowed garage in Cambridge, England, where young technology graduates built an amplifier with a power transformer shaped like a donut. Cambridge says the P40 of 1968 was the world's first amplifier with one of these toroids. The company still designs around keeping noise and distortion out of the music. A transformer can leak hum into nearby circuits, so the Edge A of 2018 stacks two toroids back to back to cancel their fields, which Mark Gusew of StereoNET says keeps interference away from the input stage. The Edge amps also shift the small distortion that amplifiers of their type make, so it only occurs where the music masks it. Alan Sircom of Hi-Fi+ called the Edge A "one of the most quiet, clean sounding, honest, accurate, detailed, dynamic, fast, coherent, open sounding amplifiers around," and Andrew Robinson heard "a little bit of warmth" in the CXA81. Cambridge suits listeners who want clean, plainly styled electronics at sensible prices.

Start with the CXA81 integrated, which Muse Kastanovich of The Absolute Sound called "the perfect start to a system that is one step up from entry-level high end." He advised against overly bright speakers and suggested adding a CXN streamer later, and Robinson found that pairing came "dangerously close" to a Naim Uniti Atom at three times the price. If you'd rather have one box, the EVO 75 and EVO 150 are streaming amplifiers with swappable walnut or Richlite side panels, and What Hi-Fi? says the 150, with its phono stage, is the one for vinyl. On a smaller budget, the AXA25 has bass and treble knobs, and Randy of cheapaudioman drove Elac Unify Reference speakers with it, never past noon on the volume. The MXN10 adds streaming to any older system, Stereophile's Tom Fine notes. The step up is the Edge A, and Roger Kanno of SoundStage! Hi-Fi likes its built-in DAC enough to recommend its digital inputs unless the source has an exceptional one.

Cambridge Audio grew out of Cambridge Consultants, a research and prototyping firm at the old Enderby's Mill in St. Ives, and Gordon Edge led the small team that became its audio division. Edge and Peter Lee kept the P40's circuit to a few transistor stages, the amplifier sold at once, and the P50 of 1970 re-engineered it for mass production. The CD1 of 1985, under technical director Stan Curtis, was the first CD player split into two boxes, What Hi-Fi? says. The original DacMagic of 1996 won Cambridge its first What Hi-Fi? Award. The Edge series of 2018, named for Gordon Edge, took nine engineers three years. The engineering team works in Cambridge and in London's SE1, and the rear panels carry their labels printed upside down as well, for reading from above. Sircom wrote that Cambridge "has long held a reputation for making affordable giant killers," and the Edge arrived in the company's 50th year.