This 3-part series serves as a high-level review of the data that has accumulated over the course of more than 10 years of clinical research with the Earlens system. Part 1 dives into the speech understanding data and how increasing the bandwidth of processed sound in Earlens results in improved speech understanding from a number of perspectives. Part 2 will discuss the perceptual benefits to naturalness and overall sound quality. Finally, Part 3 will explore how the research evidence can be explained in terms of the restoration of specific and overall loudness via the CAM2HF fitting algorithm, and how this approach to overall audibility improvement is reliably achieved in Earlens fittings via direct drive.