Getting HF Response Right in Headphone Drivers

High-frequency response above 8 kHz is critical to sound clarity and stereo imaging in headphones, yet most drivers struggle to reproduce it cleanly. Our latest white paper examines why peaks and valleys appear in this frequency range and what it takes to eliminate them.

The paper identifies two root causes: breakup modes in the driver diaphragm itself, where sections move out of phase at higher frequencies, and reflections from the headphone housing and outer ear geometry. While the latter is difficult to control, diaphragm-induced resonances can be addressed through material choice and geometry – specifically, by using stiff composite materials optimized with finite element tools such as COMSOL.

To demonstrate what is achievable, we present a frequency response measurements of our Ø40mm carbon composite headphone driver. Measured both in free field and via a 711 coupler, the driver shows deviations no greater than approximately 3 dB above 8 kHz, with very low Q-factor resonances – translating to natural, coloration-free sound reproduction with preserved stereo directivity.