What's harder on the ears?
The pop of the fast burning powder in light weight loads or the crack of the supersonic light bullet?
Does it makes sense to carry a round that is just slightly slower than the speed of sound to prevent hearing damage?
All handgun rounds will damage your hearing if you lack hearing protection.
A few decible reduction does not put in safe territory.
Check the link below to get an idea of the level of sound pressure of many firearms cartridges.
NRA Life Member - Orange Gunsite Member - NRA Certified Pistol Instructor
"When plunder becomes a way of life for a group of men living together in society,
they create for themselves in the course of time a legal system that authorizes it and a moral code that justifies it." Frederic Bastiat