“…In addition to the input-dependent gain-frequency response prescribed by the fitting rationale, most modern hearing aids include various types of adaptive signal processing to address specific needs in certain sound environments. Features such as noise reduction and adaptive directional microphones will change the gain depending on the characteristics of the sound environment in order to meet the assumed needs of the user in specific environments (e.g., Bentler, 2005; Chung, 2004; Desjardins, 2016; Neher, Wagener, & Fischer, 2016). Furthermore, sound-classification systems have been developed to classify different sound environments into a number of predefined categories that are associated with different settings of the hearing-aid parameters (e.g., Alexandre, Cuadra, Rosa, & Lopez-Ferreras, 2007; Büchler, Allegro, Launer, & Dillier, 2005; Nordqvist & Leijon, 2004).…”