The image has 5-6 ripples, so the velocity of the ejecta/sound is ~0.05c. ...5% of the speed of light by grosss averaging. Here's a tech's image indicating the density peaks taken from the second image. Images from the linked article...
Caption:"The Chandra data show sound waves rippling through hot gas that fills the Perseus cluster. The features were discovered by using a special image-processing technique to bring out subtle changes in brightness."
"Is this image you are talking about a simple time lapse image acquired over the 53 hours; or is it more like a race track photo finish image?"
53hr shutter speed on an object ~250Mly away...
So
ripples are waves? I just am not familiar with the use of the word
ripple as a scientific term.
I would note that the ripples are not concentric and diminish abruptly rather than with distance. I don't see yet how one can associate this image with a wave generator. I also don't see how you come up with a velocity for the "signal" being suggested.
ML/NJ