And there's more
Originally Posted by Bilavideo
Headphone sound is different from natural sound because recorded sound is different from natural sound.
This is true, but the differences we're talking about are mainly those between headphones and speakers (many of which happen to also apply to headphones and natural sound).
This reminds me of another concept that parallels what I was talking about above: Binaural recording technology
. The best binaural recordings are made using mics installed in the ears of an acoustically-realistic artificial head, so that all of the acoustics outside the middle ear shape the recorded sound. This way, when played back on normal headphones that project most or all of the sound directly to the middle ear, it simulates being there. The realism is only limited by the response of the mics and headphones, and the closeness in shape of the dummy head and ears to the listener's. Headphones that project the sound so that it interacts with the listener's outer ear are likely to lessen the effect (if the listener's ears are similar to the dummy's) because they add acoustics that are already approximated in the recording. Similarly, when played on speakers, adding the acoustics of the room and your head and ears to the acoustics present in the recording, as well as crossfeed and the much different placement of the speakers, causes binaural records to sound unnatural.
Most music is recorded and mixed to sound its best on stereo speakers, so when you take away the acoustics (and crossfeed and frontal positioning) by using headphones, it sounds less realistic. S-Logic and similar systems attempt to restore at least the outer ear acoustics to create a more natural sound, and probably work their absolute best with binaural recordings that use somewhat forward-facing mics just outside the ears, but also with well-mixed stereo recordings.
S-logic also involves the emphasis of certain frequencies in order to increase clarity without increasing the overall SPL. Again, a technology that's pretty simple to understand
without going into all the technical details. For me it mainly comes off as peaky treble response, but I may be a rare case (a story for another thread and another time).