Introduction

Margules ́ technical design philosophy, ANA® (Aligned Neuro-Acoustics), has resulted from an objective analysis of how humans perceive sound, and the need to understand the existing discrepancy between the perception of sound reproduction quality versus current methods of measurement and evaluation of sound “fidelity”.

The guiding principle of ANA® is to create technology that can produce an organic, realistic, dynamic and natural sound that generates a link between the source of the sound and the listener. ANA® serves to create sonic characteristics based on the meticulous care of the harmonic structure, not on the fundamental tone.

The objective of this document is to present some of the reasons why many of the measurement techniques still being used to represent the quality of audio equipment or a concert hall are insufficient and should not have the relevance that they are currently granted. These measurements have been erroneously considered as primary and reliable references to determine the perception of the quality of reproduced sound, often leading to incongruent results during listening tests.

The concern to understand the deficiencies and limitations of current measurements used to portray the quality of sound reproduction, which do not highlight the importance that should be given to the care of the harmonic structure, has resulted in the conceptualization of a distinctive characteristic that should be given much greater relevance: engagement.

An engaging sound is distinguished by characteristics that differentiate it from sounds that are naturally considered as trivial or relatively unimportant, because an engaging sound is directly linked to our primary survival instinct, which pays most attention to nearby sounds that might have an immediate impact on our survival, as opposed to paying attention to sounds that are perceived as distant and/or of minor importance.

Engaging Sound

David Griesinger’s studies on phase coherence serve as a reference to measure the quality of sound reproduction, and for the purpose of this document we will define an engaging sound as one that demands our attention and retains it- what the same author refers to as «engagement» in his works, such as in “The Physics of Auditory Proximity”; that is, the perception between distance and intelligibility. By contrast, distant sounds, even when they are intelligible, may not attract our attention or can be easily ignored.

What makes sound ”engaging”?

Perceiving a sound as engaging, and its counterpart as muddy or insignificant, is related to the perception of proximity, since sounds perceived as closer are the ones that demand our attention.

Almost instantaneously, humans perceive nearby and distant sounds of any intensity. Curiously, this perception of distance or closeness of a sound can occur with only one ear or channel. This characteristic supports the conclusion that the perception of distance and positioning of a sound source is mainly related to phase coherence of the harmonics and the fundamental.

There are methods to evaluate sound intelligibility («CLARITY 80» Method), but not to measure an engaging sound, which is mostly associated with sound proximity and clarity. In fact, there are concert halls with a sound signature that could be described as intelligible but not engaging.

An engaging sound is mostly related to the way our brain processes the information from sound waves through the ears. Nearby sounds are characterized by being easily located, and the position of the source can be identified, primarily, by direct soundwaves rather than by reflections.

Studies have shown that we perceive the source or location of a sound more easily by the harmonics than by the fundamental tone. Equally important, harmonics also allow the listener to identify sounds much more than do fundamental tones, making harmonics by far the most important goal in achieving realistic reproduction of music.

ANA® (Aligned Neuro-Acoustics) is a design philosophy to develop technology that prioritizes the harmonic structure over the fundamental tone to achieve realistic sound, providing appropriate frequency response, low distortion, accurate harmonic reproduction, while optimizing the relationship between source and listener.

Whereas improvements in any field are a continuous process, there are already a few very convincing and thoroughly satisfying musical results available now, thanks to the efforts of highly dedicated and accomplished electronics designers.

However, most current design goals and measurements for audio gear are done basically over the fundamental note, which does not give a complete understanding of the sound quality. This explains why most audio equipment measures very well, under the usual standards, but does not sound engaging and does not create a bond between the listener and the performer – which in our opinion is the main goal of audio equipment meant to listen and enjoy the music.

Margules® is working with a team of engineers and neurologists to publish a white paper to further explain ANA® and present technical findings, which in turn will produce reliable criteria to consistently measure very natural and truly musical reproduction, with the ultimate goal of benefiting all music lovers.