Raal Requisite SR-1A True Ribbon™ SR1a. The world’s first Earfield™ headphone monitor. The SR1a by RAAL-requisite is the world’s first Earfield™ headphone monitor. Experience mixing, mastering, and home listening with unparalleled accuracy and realism in a soundfield devoid of room acoustics and comb-filtering caused by work surface reflections. Earfield™ technology delivers unheard of program accuracy and a [...]