The difference is independently certified ISO 23351-1 DS,A performance versus a marketing description. “Comfortably quiet,” “excellent acoustics,” and similar descriptions tell you nothing about the actual acoustic performance — they are subjective characterisations that cannot be tested or compared. DS,A under ISO 23351-1 from a named accredited laboratory is a verifiable, comparable specification. HIGHKA’s DS,A = 29.4 dB (SGS-verified) means that in a 65 dB open-plan ambient, the pod interior measures approximately 36 dB — a specific, independently verified performance that the Irrelevant Speech Effect literature links to effective ISE elimination and cognitive performance restoration.