Devices and method for obtaining or providing listening or detection of audio frequency modulated optical energy including, involving, utilizing, facilitating and/or providing an interface (including electronics) configured such that when operatively connected to individual or groups of elements of one or more solar arrays (or cells, photodetectors, or other optical sensor device), respectively, the interface and the solar array(s) together function, responsive to sensed audio-frequency light intensity fluctuations of an optical signal received by said solar array(s), as a remote acoustic sensor (RAS)-based device.