When a musician, but also a sound designer, a sound engineer finds a need to describe what they feel, to represent the acoustic world they live in, the natural means are not sufficient. In our visual and linguistic system any artificial device is used in order to upgrade, to amplify and to render the effect of the visual action more effective, in search of a more real rappresentation of the real world, in search of one effective expression. This allows us to imagine that, within precise limits, also the nature of a musical event can be extended, be optimized, be magnified.

Structures of distortion of the temporal dimension in which the musical events exist have place, derived from the natural acoustic experience of the great caverns and other natural atmospheres: the echoes and reverberation. It is also true that the reconstructions of these structures, in different ways and various shapes of realization, have existed in every time. The experience of the mysterious in fact, often is not easy rappresentable with ready means, or natural. A well taken care of planning is necessary, examples of many buildings in which the result  has been definitive are in front of us.

We can comprise these acoustic experiences in many buildings of recent construction: The cathedral of Saint Paul in London, the Statuary Hall of the Capitol in Washington, la Grande Salle in the Louvre to Paris, Saint Giovanni in Laterano in Rome, the cathedral of Agrigento. I say just recent because they find themselves on the hem of a suspension of the acoustic plan of the architecture, in favor of a much more visual one and founded on the graphic design of the plan. Naturally on this higher level there is not a true separation between the visual conditions and the auditory ones.

In the antiquity impressive examples of acoustic planning are the wonders of the Greek theatres, in particular, even if for different reasons from those illustrates before, the Theatre of Asclepio in Epidauro in which everyone of the 14,000 spectators  can easily feel one word whispered on the proscenio. But it is the extraordinary echo, repeated seven times only under the apex of the main cupola in the Mosque of Shah Abbas di Isfahan, the mirabile object of the construction of an acoustic atmosphere, in this remarkable place appears obvious that is not the sound the product of the visual structure, but is instead a lot probably viceversa.