Fig. 1

Spectrogram pre- and post-noise reduction showed at their original 20 Hz sample rate. Spectrogram of IO6H1BDF prior to acoustic noise reduction (Raw) and then processed three separate times (individual, batch and batch adaptive) with RX6 Spectral De-Noise module. The processed files were resampled back to 20 Hz and the spectrogram generated. The section of the audio file used to generate the noise profile used is highlighted in the top panel (I06H1BDF Raw) between 09:45:58 and 10:02:40 and the range of expected arrivals based on the reported eruption time based on a range of celebrities from 0.25 to 0.4 km/s are plotted as red lines at 09:38:10 and 10:40:05