Pro Audio Technology SCRS-25im In-Wall Speaker – Introduced during CEDIA 2017, the SCRS-25im in-wall loudspeaker is Pro Audio Technology’s most affordable speaker. Utilizing a ¾-inch high-frequency compression driver that resides in a Pro Audio Technology designed horn and a pair of 5-inch, long-throw paper cone woofers, the SCRS-25im is a high-efficiency speaker rated to produce a frequency response of 80Hz to 18kHz, according to the California-based company. proaudiotechnology.com