For the first time the dynamics and frequency of shock waves generated from the implosion of cavitation bubbles were resolved using ultra high speed camera recordings and acoustic pressure measurements. In particular, shock waves cavitation-induced in water from a 24 kHz source, lead to a strong pressure peak in the pressure spectrum, around 3.2-3.4 MHz while shock’s maximum pressure amplitude fits well with 1/𝑟 scale, confirming that this is the reliable scale for the proximal distances (1–10 mm) from the sonotrode.

Understanding the behaviour of shock waves opens novel avenues to technologically important applications of shock waves such as lithotripsy, ocular surgery, pharmaceutics, sono-exfoliation of 2D nanomaterials and cavitation melt treatment, to name but a few.