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Andrea von Salis Hi-End Audio Software for MAC

 The AVS reproduction system
Gubert’s square


The reproducing system provided by the AVS theoretic model works using both conventional recordings (mono, stereo, surround) and the signal, recorded in conformity with the AVS system, stored in the two audio channels of any software medium (CD, SACD, vinyl, MD, Laserdisc, DVD, DAT etc...).
The system is composed of two front channels and two rear channels:
therefore it uses four loudspeakers, four power amplifiers and a MAC computer with the AVS 3D●VR software, that is able to reproduce perfectly equalized the two front channels and modifying them in order to be send to the rear ones (R & L).
The signal coming from a source (i.e.  a MAC internal audio-video player or an external CD player ) is sent to the front channels (R & L) without alterations (equalized if you want), while rear channels are driven by the Correlation Controls of AVS 3D●VR software that takes care of re-calibrating some parameters of the signal (frequency response, delay time, phase), in a variable way according to the psychoacoustic effect we are wishing to obtain, and then sends it to the rear channels.
This technique allows to obtain phantom information separation by correlograms
from AVS recordings as well as to extract much more information and a totally 3D sound-stage from
conventional software: listen to understand.

Rear channels have then the function:

● to widen the soundstage
● to reconstruct a phantom centre/front image
● to increase and redefine micro-information extracted from software

The result is:

● a "Three-dimensionization" of the soundstage, in accordance with purely psychoacoustic parameters:
   AVS 3D;
● a mental "Visualization" that completely involves the auditor: AVS VR (Virtual Reality).

Three-dimensionization of the soundstage

By this adjustment of the correlation controls present in the AVS 3D●VR software, suitable for all existing conventional record standards (mono, stereo, surround), you obtain a sensation of a substantially three-dimensional reproduction of all the soundstage, in part behind the listener as well, with many sound quality improvements, aimed at making the listening experience on the whole more faithful to the experience of a live performance.

The system's "Three-dimensional mode" (AVS 3D) allows to obtain the following improvements in the sound reproduction, in comparison with a normal stereophonic reproduction:

improvement of the sound scene (soundstage), that becomes totally three-dimensional and is reconstructed, with surround software behind the listener as well, with "normal" software as far as the listening position and at least 180° "opened";
increase of the three-dimensional perception of the sounding subjects positioned inside the soundstage;
 widening of the listening position in which a likely soundstage reconstruction is obtained;
total tone consistency at any sound pressure level;
increase of the perception of bass frequencies (20-100 Hz):  no subwoofer is needed;
increase of the micro-information quantity and quality, giving a better body of the sound as a main result;
feeling of improved fidelity of the listening experience, quite independently of the frequency response of the reproducing system. All described improvements are more and more evident according to the quality of the reproduced recordings.


Soundstage created by an AVS system with conventional recordings. The theoretical soundstage is developed as far as the listening position and “opened” at least 180° in front of it. Optimal listening area (blue), soundstage reconstructed by rear speakers (gray).
“Virtualization” as mental/virtual reconstruction of the sound event

By a different adjustment of the correlation controls present in the AVS 3D●VR software - tuning them for AVS recordings (but it work also for particular stereo and/or AV soundtracks) - the usual sound perception field is "surpassed"; that leads our auditory system to "work" in conformity with a different sound information processing model. What happens quite of its own accord and almost inadvertently in a space of 1 seconds till 15 minutes dependently on the subjects (only at the first listening session), is a new experience. At least a fuzzy wandering and hazy sound is possibly heard; a clear perception of sound localization is missing: the two images have not yet been correlated. Suddenly, when the two images (frontal and rear) are "linked" by our mind, the confusion turns into a perfectly sharp soundstage, most steady, felt as absolutely faithful for sound quality, and totally disconnected from the reproducing equipment, with a connected sense of general well-being.
At this point the sound of the reproducing system cannot be distinguished, on the point of view of realism, from the one of the surrounding world/environment. All the improvements described in the "AVS 3D" mode are further emphasized. 

By the correlation controls present in the AVS 3D●VR software it is possible to link the frontal phantom image  to the frontal image created by the front speakers, obtaining a correlation between three-dimensional images (frontal and rear). The result is a sound hologram soundstage, extended all around the listener and stable even at listening positions very far from the “hot” point: only the perspective changes, as it would happen moving around in the place where the recording was made. This happens thanks the unfolding of a primary mental field which the subject feels to be part of it. In this mental state the three-dimensional reconstruction of the sound subjects inside the field happens following elaboration processes that the mind utilizes during fetal/neonatal life and during dreams. 

The soundstage re-created at the listening position by the AVS system driving rear channels only (gray), once the mind has shifted in the “dreaming” modality to reconstruct a field of events. Part of the scene is reconstructed in front of the listener and it appears as a “phantom” scene. The mind reconstructs a virtual coherent sound-field in a mental space that is similar to the one that unfolds during dreams.