STC stands for “sound transmission class”. It represents a method of measuring sound transmission loss through a barrier ie. a door or a wall. The higher the STC rating the better the sound deadening property of the door. AMBICO provides 1 3/4″ thick doors from STC 33 to STC 53. Doors up to 6″ in overall thickness provide a rating of STC 56. Let us help you select an acoustic product that will meet your project requirements.