In cases like this it is usually the recording mic techniques of the mix. There will usually be effects like this that differ from recording to recording. My interest in is general effects that are recording independent as these have implications to the loudspeaker design. Specific effects on a single recording, while interesting and pleasurable, are still quite specific.Have you ever noiced how the sound of some recodrings "locks in" with at a particular level setting. And how this differes with the recording. I tend to think that this level is the level at which the recording was mixed and the mix just sounds better at that level. This too is not a loudspeaker function however.