Then when increasing the acoustic drive amplitude, we are interested in the response in the bubble radius. Figure 4 shows the drive amplitude and the response in the PMT. What was observed was the peaks of the drive amplitude coincided with sharp spikes in the PMT and these coincide with the occurence of sonoluminescence. Here it can be seen that there is some noise and background effects taking place but a clear alignment of sharp peaks with the maxs of the drive amplitude.