C803AT72 8" Coaxial Loudspeaker with 25V/70.7V-4W Transformer by Atlas Sound A high-quality 16-watt loud speaker with a factory-installed 25/70.7V 4W line-matching transformer.It is ideally made for Multi-Purpose Commercial, Industrial, and Institutional Use and its performance is proven with its Wide Frequency Response. The model has a Post-Mounted Tweeter which Adds Strength and giving it a Beautiful performance. Model C803A mounts a wide variety of Atlas Sound baffles and enclosures, with the optimum sealed enclosure size being .36 cu. ft.