When buying audio gear, specs like frequency response, impedance, and driver size can be confusing. But they matter. Frequency response (like 20Hz – 20kHz) shows the range of sound your device can produce. Impedance (measured in ohms) affects how much power your headphones need — higher impedance usually means better quality, but they may need an amplifier. Driver size (in mm) plays a big role in sound output — larger drivers often deliver better bass and clarity. Sensitivity (in dB) indicates how loud headphones can get. Knowing these specs helps you make smarter audio choices — not just follow brand hype.