An auditory enhancement is an increase or improvement in the detail and clarity of sound.  This can result in the person becoming extremely aware of all the sounds around them with an enhanced ability to comprehend multiple layers of sound and better identify their direction and location.
The most common manifestation of this effect is a greatly enhanced appreciation of music. This can allow people to experience music in a level of detail that is unparalleled during everyday sober living.
Auditory enhancements are often accompanied by other coinciding effects, such as auditory distortion and auditory hallucinations  . They are most commonly induced under the influence of moderate dosages of psychedelic compounds, such as LSD, psilocybin, and mescaline. However, they can also occur less commonly under the influence of stimulants, cannabinoids, and dissociatives.
-  Juszczak, G. R., & Swiergiel, A. H. (2013). Recreational use of D-lysergamide from the seeds of Argyreia nervosa, Ipomoea tricolor, Ipomoea violacea, and Ipomoea purpurea in Poland. Journal of psychoactive drugs, 45(1), 79-93. | https://doi.org/10.1080/02791072.2013.763570