@lewm , really? Some speaker manufacturers, to make their speakers sound better at low volumes and reduce sibilance tuned their speakers with a built in Gundry dip. Wilson did this with the Watt/Puppy. It is just another application of Fletcher and Munson's research. I'm not entirely sure but I think the BBC first started doing this in broadcasting or in their monitors maybe both.
It seems that many people here are talking about distortion not true sibilance.
It seems that many people here are talking about distortion not true sibilance.