THX Onyx DAC

Best known for its enormous surround sound systems in cinemas, THX also makes this ultra–portable DAC for personal use. The Onyx is so small that it just looks like a little cable, and has a USB–C port for connecting to Macs or iPads that have USB–C. There’s a USB–A adaptor for older Macs too, although iPhones and iPads with Lightning will need one of Apple’s Lightning adaptors ($29 or $39). The sound quality is impressively clear and detailed, and the Onyx also includes an amplifier to give your music some extra power and volume. That compact design and powerful output make it great for exercising, but the Onyx takes its power from a device’s USB–C port, so some people may prefer a DAC that has its own rechargeable batteries for longer journeys.