Sound equates to power? Huh? Since when does the power of an
engine equates to how much sound it generates?
It might mean Rafale's engines are powerful (and the trust to
weight ratio is excellent), Rafale might be able to take off with
military power, does not need afterburner, etc.
From what you have said, I would say that Rafale's M88 engines are
indeed very good. I can image the M88-3 even being better.
As for the NGF competition, I can see Rafale having a very distinct
advantage, but of course it all comes down to Price to Technology
ratio and how good DSTA perceive the offer is.