Benson Wong told the retailer Apos Audio that he collected vintage Stax headphones long before he made any, and one model was always missing from his shelf. Stax made only 600 of the original Omega, so he had almost no chance to hear one. His curiosity about it started him building headphones of his own, drawing on what he learned repairing headphones for fellow collectors, and that became ES Lab. An electrostatic headphone makes sound with an ultra-thin film that carries a high-voltage charge and hangs between two perforated metal plates, and the music signal on those plates pushes and pulls the whole film at once. The Omega used wire mesh for those plates. Wong chose copper plates instead, which he told Apos are easy to drive and give excellent bass and soundstage. Oscar Stewart of Hifi Pig, who says electrostats are not usually his thing, called the ES-2a "the first electrostatic headphones I have genuinely enjoyed long-term." ES Lab suits listeners curious about electrostatic sound, and Stewart heard the ES-2a at its best with jazz, folk and acoustic music.

Start with the flagship ES-2a. Headphones n' Stuff heard it improve on the ES-1a in every area and called it "unmatched in terms of electrostatic price to performance." It comes with cloth filters that fit inside the pads. Taking them out tips the treble up slightly, and the reviewer, who listened mostly without them, suggests treble-sensitive listeners try them in. Like any electrostat, it needs its own amplifier, called an energizer, and it uses the common 580-volt Stax Pro Bias standard with a five-pin plug. Sine Craft Audio drove the ES-2a easily from an LTA Z10e and found it was not a "power-hungry beast." Give it some volume, since Sine Craft found electrostats get fuller faster than they get louder. ES Lab's EHT-7 transformer box lets a speaker or headphone amp you already own drive electrostatic headphones. On a used ES-1a, fit the dark fabric pads, which Headphonesty says almost everyone prefers, and use a powerful energizer, as Headphones n' Stuff advises.

ES Lab still repairs headphones, the work it grew from. Its Hong Kong workshop has a clean room and the film tensioning and coating equipment needed to rebuild electrostatic drivers, and it services Sennheiser HE90s, Sony MDR-R10s and Stax models. Wong told Apos that fixing cracked frames and worn coatings taught him a headphone has to last as well as sound good, so ES Lab's drivers come fully apart for service, and he says the company still services its earliest units. He also described how ES Lab modified an industrial paper embossing machine to press a pattern into the thin dust screen in front of the driver, which let ES Lab make it thinner and more consistent. The ES-R10, a dynamic headphone, pays tribute to Sony's 1989 MDR-R10, with cups shaped from optical 3D scans of the original and made from the same zelkova wood. Kyle of Den-Fi wrote that its echo comes closer to a concert hall than any headphone he had heard. Wong told Apos that tribute products will stay the theme of ES Lab's roadmap.