My almost exclusive listening is to classical, where the peak loudness in a concert is very loud

 

Au contraire, my friend - just as ambient road noise is much louder than people think, concert hall SPLs are lower than people think, even in the middle of the orchestra. Here's a great study done on members of the Chicago Symphony Orchestra. It documented a maximum transient peak of 115.5 dbA using RMS-equivalent sound levels, and the highest SPLs were in brass and percussion sections "and for those instruments seated in front of them". The biggest grand piano can't top 95 db. Using the max RMS method, max peak levels were 106.4 dbA and 8 hour equivalent daily exposures had a mean of 85.5 dbA.

 

There are many such studies and they all show the same thing - compared to many OEM and most aftermarket car audio systems, live symphonic music isn't that loud even sitting 2 feet in front of the horn or percussion section. And you have to remember that these #s are for the players. The audience is significantly further away from the sources.

 

Sound levels are not additive - 3 horns each playing at 75 db do not create 225db of sound. If they're all emitting the same frequency spectrum at equal volume, they'll theoretically generate an 81 db SPL (75 + 3 + 3 db). But phase differences between them will combine with environmental factors like reflection, damping, and absorption to reduce that. And the contributions of quieter instruments to the cumulative SPL are miniscule - a violin generating a 75 db SPL tone at the measuring point will not materially increase the SPL if added to a trumpet blaring at 95 db. Further, sound energy decreases as the square of the distance from the source increases - so the audience is getting far less energy than that to which the players are exposed. Here's a detailed list of average and peak levels by instrument from 2 professional symphony orchestras (Schmidt et al. Sound Exposure of Symphony Orchestra Musicians. Annals of Occupational Hygiene 55: 893-905, 2011):

 

 

The loudest widely known pieces include Mahler's 8th (originally performed with about 1000 players), the 1812, Beethoven's 9th, Shostakovitch's 10th, Carmina Burana and Holst's Planets. And there are many obscure pieces (e.g. Corigliano's Circus Maximus) that really blare at you. But very few classical pieces expose any audience member to SPLs above 95 dbA even on the loudest peaks.