Since the first Revel speakers in 1996, Revel products have stood at the forefront of loudspeaker design and performance. Revel in-ceiling loudspeakers draw upon the same research, resources and unique perspective that put all Revel loudspeakers in a class by themselves. Revel in-ceiling loudspeakers provide unparalleled value and are known for their standard-setting low sonic coloration and their freedom from distortion over an extraordinarily wide dynamic range.Long-throw woofers with cast frames and rubber surrounds provide high output with low distortion. 1-inch (25mm) angle-adjustable, metal-dome tweeter with an integrated waveguide provides optimized response both on and off axis. High-order crossover network with premium-quality components delivers extraordinarily accurate timbre reproduction. Boundary compensation switch (C783/C763) lets you adjust the speaker to maintain tonal accuracy when the speaker is placed near a wall. Three-position tweeter level control (C783/C763/C583/C563) lets you adjust for optimum response in a variety of acoustical environments, or for using the speakers without grilles.