Haas zona, reverberacija, decay u kontrolnim sobama

[NLP]

2. deo

Haasova zona nije baš zabetonirana, oko 5-40ms.
Između 18-35ms je za režirke odlična, odvisno i od kubikaže prostorije te tretmana.

Stranica 27 sa RPGj-evog pdf.-ja:

"Why doesn’t the room sound anechoic with room reflections
30 dB below the direct sound?
�� Possible reasons:
�� The 35 ms integration time of the ear may raise the level and
importance of the diffuse sound field
The diffuse sound field is very dense and occurs without any
time delay, as in a reverberant space which requires time to
develop a reverberant sound field
�� It’s like adding reverberation with a level 30 dB below the
anechoic direct sound, an interesting perception experiment to
perform."

I još sa strane Altona Everesta:

"Small critical listening environments are spaces such as recording
and broadcast studios, residential listening rooms, and music practice
rooms. In concert halls, these spaces are usually designed to be neutral,
adding little of the signature of the room to pre-encoded reproduced
sound. A method to achieve this was described by Davis and
Davis in their live end–dead end control room design concept.3 An
abbreviated list of two of the room criteria follows:

There (should be) an effectively anechoic path between the monitor
loudspeakers and the mixer’s ears for at least 2–5 ms beyond the studio’s
initial time-delay gap. There (should be) a highly diffused sound
field present during the initial onset of the so-called Haas effect.

In 1984, D’Antonio et al.4 extended the ideas of Davis and Davis3 by
introducing practical ways to provide a temporal reflection-free zone
(RFZ) surrounding the listening position using flush-mounted loudspeakers
and a diffuse sound field using reflection phase grating (RPG)
diffusors on the rear wall. The RFZ is created by splaying massive,
speaker boundary surfaces, which may also contain porous absorption
to further minimize the speaker-boundary interference. The RFZ also creates an initial time delay before the onset of the diffuse energy from
the rear wall. The rear wall diffusors create a passive surround sound
and a diffuse sound field for the room. They also widen the “sweet
spot” and provide low-frequency absorption below the diffusion
design frequency. Over the past decade this design has proved to be a
useful approach to designing listening facilities and has been used in
over a thousand facilities.
In small critical listening rooms, the geometry, close proximity, and
surface topology of the boundary surfaces to the listening position may
result in a very sparse temporal and spatial distribution of reflections.
The nonuniform reflection pattern can result in specularity effects,
such as comb filtering and image shifting, as well as nonuniform
sound distribution throughout the room."

Vir: Alton F. Everest; The Masterhandbook of Acoustics, fourth edition: stranica 499 i 500.

A RT60:
"Reverberation time is defined as that time required for the sound in a room to decay 60 dB".
je priporučljiv od otprilike 0.3 - 0.5 sekunde odvisno opet od kubikaže režije, tipa produkcije.


Svejedno je prva prioriteta napraviti sa akustičkim tretmanom dobru frekvencijsku linearnu sliku (u okvirima -/+ 5-15dB max.) i onda paziti na zdrav RT60 kroz čujni spektar u režijama i na tih Haasovih 18-35ms.
Jer ako je soba mala onda nečete moči dosegnuti takve normative, logično.

Eto, da je bilo brže podao sam direktno na engleskom inače bih se napisao...
Oprosti dema još jednom, nisam namjerno i hvala!
Nadam se, da sam popravio krivicu.
Čovjek sam pa pravim greške.