The antonyms for the phrase "rise to crescendo" would be words that convey the opposite of building or intensifying to a climax. Words like decrease, decline, diminish, decrease or fall do not match the meaning of the original phrase as they imply a reduction in energy or intensity. Another antonym could be plateau, which suggests a level of stability and consistency, rather than an increase in intensity or volume. The opposite of rising to a crescendo could also be described as fading away, losing momentum, or simply staying the same. These words provide a contrasting meaning to "rise to crescendo," which implies a dramatic and energetic build-up of sound, emotion, or intensity.