>Is there an objective way to measure this so someone would know it's getting worse? In principle it should be possible to do standardized testing of any set o

>Is there an objective way to measure this so someone would know it's getting worse? In principle it should be possible to do standardized testing of any set of headphones or earphones with a properly designed Dummy Head, similar or the same to what is used for things like generating binaural audio recordings. There at least were a number of major Dummy Head designers back when I last looked for something else, though I don't know what the current state of the market is. But basically you have something that physically simulates a human head, including both physically simulated ear pinnae and the ear canals, with microphones embedded within them that have a high enough res and response to completely cover the human discernible audio frequency range. Obviously it won't tell the exact effect for any given individual because the shape of our ears varies. But it would be possible to have a completely open 3D/material/mic standard that would cover the max range, and could then be used to quantify and objectively compare all aspects of head mounted audio products, not just noise cancellation but audio reproduction. I assume this isn't a thing already in part because a lot of manufacturers are perfectly content without universal objective comparisons, since that would reveal a lot of high cost kit that isn't actually delivering any gains.