A cloud-based HRTF repository system that can be accessed via a public application program interface (API) on the remote repository server to permit individual users of audio-capable client devices to upload and store personalized HRTFs and basic device data in an open format. The cloud server repository includes a computer readable non-volatile memory which further includes a program memory portion comprising an application program interface (API) module configured for receiving HRTF data from a client device, or from a brand manufacturer, and for sending HRTF data to a client device. A brand manufacturer can upload HRTF data to the cloud-based HRTF repository system either directly from their branded companion app in a client device, or optionally via their own cloud server. One technique includes using a Media Service Provider (MSP) app in the client device with a provided server access library (SAL) thereby enabling retrieval of HRTF data for bath a personalized HRTF for any brand client device, or for retrieval of generalized HRTF data by brand manufacturers having a SAL in their brand server via the remote server repository public API.