I mean, we’re talking half as loud. I would have thought to a layman it would be a lot more impressive to remove half of a loud sound than half of a quiet one. But I’m wrong on that one judging by your comment, which is fine. To a noise control engineer whether the sound is loud or quiet makes no difference to how impressive it is because these are linear systems (unless we are talking extremely loud e.g. >140dB). Good point on the obvious measurement location.