Fadeout is a term that describes the gradual decrease of a sound or image. It implies a steady weakening or gradual disappearance of something. On the other hand, antonyms for fadeout could be strong or vigorous, or vivid and bold, signifying a sharp, concentrated and intense sound or image. It can also be described as steady, continuous or sustained, implying stability or consistency. Another antonym could be loud or bold, indicating a clear and distinct sound or vivid image that demands attention. Conversely, faint or soft, is a related antonym indicating a diminished or subdued representation of sound or image. In short, the antonyms for fadeout all bear a sense of clarity, steadiness, and intensity.