The founder of boutique brand Cavalli Audio and a longtime favorite of the audiophile community, Alex Cavalli has, by all accounts, a pretty impressive background. He earned a PhD in plasma physics from Dartmouth, where he also studied thermonuclear fusion. He then worked on CAD software and semiconductors, and went on to help create one of the first internet search engines and commercial-quality web browsers. But it wasn’t until his son needed an idea for a science project that Cavalli revisited his first passion: tube amplifiers. He had experimented with tube amps when he was a kid and was surprised to discover that they’d seen a resurgence over the years as headphone amps. Smaller and easy to work with, tube headphone amps had inspired many new manufacturers and a vibrant DIY community, and Cavalli decided to get in on the fun.