Contribution
HRTF Measurement System with Rotating Loudspeakers
* Presenting author
Abstract:
Measurement of Head-Related Transfer Functions (HRTFs) is often lengthy and thus prone to errors from unintended head movements. An HRTF measurement setup has been developed in the Audio Information Processing Group (AIP) at the Technical University of Munich which uses a movable arc around the static subject, thereby minimizing subject body and head movements. An installation supports the arc in AIP’s anechoic chamber; rotary modules are chosen to ensure compatibility with the measurement construction. The system utilizes 32 elevational loudspeakers, ranging from -76 to 88 degrees, with a custom-designed enclosure that meets the required frequency characteristics for accurate HRTF capture. Excitation signals were optimized to reduce measurement time while maintaining the signal-to-noise ratio (SNR) at the desired level. A custom interface was developed to unify all calibration steps, arc control, and measurement procedures, allowing efficient adjustments in measurement speed and resolution. With the current parametrization, a 5-degree azimuthal resolution HRTF measurement of 2304 points can be completed in under 11 minutes, maintaining an SNR above 30 dB across all critical bands. This approach significantly improves measurement reliability and efficiency, advancing HRTF applications in spatial audio research.