Thanks for the translation.... 😊
Save there is other means of controls in acoustic, and others in mechanical and electrical dimensions for sure...
A remark:
If you coupled this Helmholtz idea with the ideas of the 2 Japanese scientists i cited already in a preceding post about the law of the first wave front and his relation to the source width (ASW)and the listener envelopement concept(LEV) who gives us a very precise set of experiments to understand how it is possible by room material treatment and by room controls to create a balance which will make us able to create an image width also compatible with an enveloping listener sound, we have some idea about how it is possible to make the room an activated entity in the recreation of sound, imaging and timbre and no more a set of passive walls...
I will give their introduction here and their conclusion....
«In 1989, Morimoto and Maekawa demonstrated that
spatial impression comprises at least two components and
that a listener can discriminate between them [1]. One is
auditory source width (ASW) which is defined as the width
of a sound image fused temporally and spatially with direct
sound image, and the other is listener envelopment (LEV)
which is defined as the degree of fullness of sound images
around the listener, excluding a sound image composing
ASW [1,2],»
«In conclusion, it seems that the results of three experiments shown in this paper evidence in favor of the hypothesis that the components of reflections under and beyond
the upper limit of validity for the law of the first wavefront
contribute to ASW and LEV, respectively. Accordingly, it
is possible to control ASW and LEV independently by controlling physical factors for each component. The important is that it is necessary to provide reflections beyond
the upper limit in order to generate LEV. Furthermore, it
is clarified that the reflections beyond the thresholds of
LEV do not always lead to disturbance. In other words,
it is possible to make the listeners perceive LEV without
causing disturbance.»
https://www.researchgate.net/publication/223804282_The_relation_between_spatial_impression_and_the_l... I will repeat what is the LAW OF THE FIRST WAVEFRONT:
«In audio in the past, the terms Haas effect and law of the first wavefront
were used to identify this effect, but current scientifi c work has settled on the
other original term, precedence effect. Whatever it is called, it describes the
well-known phenomenon wherein the fi rst arrived sound, normally the direct
sound from a source, dominates our impression of where sound is coming from.
Within a time interval often called the “fusion zone,” we are not aware of
reflected sounds that arrive from other directions as separate spatial events. All
of the sound appears to come from the direction of the first arrival. Sounds that
arrive later than the fusion interval may be perceived as spatially separated
auditory images, coexisting with the direct sound, but the direct sound is still
perceptually dominant. At very long delays, the secondary images are perceived
as echoes, separated in time as well as direction. The literature is not consistent
in language, with the word echo often being used to describe a delayed sound
that is not perceived as being separate in either direction or time.Haas was not
the first person to observe the primacy of the first arrivedsound so far as localization in rooms is concerned.»
Sound Reproduction The Acoustics and Psychoacoustics of Loudspeakers and Rooms Floyd Toole Chap.6 P.73