[earthicus]

I know nothing about acoustics and its units - the abstract of actual paper says more precisely that it reduces the 'acoustic energy' by 94%, not the power. Can you convert this to a decibel figure? Would you mind explaining what these units mean and how you do the conversions?

[chrismorgan]

It’s a logarithmic scale, which is reasonably approximated as an increase of 3 dB doubling the power (“acoustic energy” is synonymous). A 94% reduction means you’ve reduced it to 6% of the original, which is about a 12 dB reduction (you can figure it in your head like so: 3 dB = 50%, 6 dB = 25%, 9 dB = 12.5%, 12 dB = 6.25%).

For more info, see https://simple.wikipedia.org/wiki/Decibel (which is much more approachable than https://en.wikipedia.org/wiki/Decibel).