Sound reproduction in cinemas has greatly improved in recent years thanks to the widespread use of broad spectrum systems and multichannel Dolby SR and Dolby SR-D and DTS systems. Similarly, the advent of DVD (Digital Versatile Disc) and its ability to decode multi-channel audio such as Dolby Pro Logic, Dolby Digital and DTS bring us increasingly to a spatialization of the sound reality that seeks new sensations in the global perception of audiovisual show.
Of course, the use of stereo sound can not be free and must be closely related to the narrative and dramaturgy project. Cases have been exaggerated stereo effects distracting and "derailing" the viewer concentration front of the screen (central conical projection).
While it has evolved into a rational use of stereo sound it would be good to reflect on the manufacturing processes stereophonic soundtrack.
Stereo and dash
It may seem strange but when a director is clear about its draft decision to use film stereo specific scenes have to be consulted in advance with the sound engineer and the Production Manager. What does not roll or stereo? After many experiences of shooting live sound has concluded that binaural is better "fabricate" in the auditorium of mixing. Roll with stereophonic microphones means strictly adhere to a technical script where the camera movements, axes, sound atmospheres and staging have to be consistent for assembly. You can not fake planes and there will be problems Raccord in the spatialization and localization of sound sources. The movie Detective (1984) of Jean-Luc Godard was written and staged to be shot in stereo, in Cinemascope and fixed planes. A stereo microphone following a panoramic camera produces a shift of funds exaggerated sound (effect of dizziness) and surely unjustified when mounting. In addition, record dialogues with stereo microphones, such as MS, is compromising too much understanding of the dialogue due to the use of a cardioid microphone to collect information M. This, combined with frames of large camera and ambient noise, may cause more problems compared to what they bring to the stereophonic record of a situation.
Stereo and shooting
Obviously the quality and richness of sound environments and acoustic certain locations recorded in stereo with irreparable in post-production. The most frequently used method is to roll the dialogues in mono or "bipista", ie, several microphones mixed in mono or check-cane and wireless (HF) separately on two tracks (left channel = reed channel right = HF). Environments Raccord and additional sounds can be recorded in stereo after finished the scene. The microphone used in general is a MS that is theoretically compatible Mono. Stereophony AB phase can present problems for encoding in Dolby A and SR system. With the new digital systems (SR-D and DTS) this problem would not arise, but some experiences in France showed that MS can produce more catastrophic effects that XY or AB stereo.
The sound environments in MS are recorded without coding and bipista (M = left channel, right channel = S) leaving the encoding for the time of mixing. The great advantage of MS compared to other types (XY, AB) is to allow open or close the stereo mixer based on taste and depending on the correspondence with the projected image.
The recent use of digital recorders to four channels allows great flexibility of sound recording. For example, record dialogues and environments at the same time: CH1 = Reed; CH2 = HF; CH3 = M; CH4 = S; 1 3 cane and HF separated, or use multiple multitrack recorders and many wireless in the style of Robert Altman.
Stereo sound editing:
One of the stages of sound postproduction that has been more favored with new digital technologies is precisely the assembly of sound. Yes, we went back a little in time, the montage in the moviola and perforated magnetic 35 mm allowed a limited number of sound bands to be heard simultaneously. Each band is composed of 3 tracks shaped like this: 1 = mix rod + HF; 2 = cane; 3 = HF. Only in the final mix and after having made the premixtures of dialogues, environments and music could you have a global idea of the sound mounted. In addition, stereophony requests double tracks for the environments and music.
This is where the non-linear editing proposes an almost unlimited number of tracks and becomes an excellent tool for a while on a "headache" for others. The simplicity and effectiveness of the soundtracks of the years 60 contrast in most cases with current, crowded and meaningless. It all sounds but who said that anything that sounds interested in history?
In the current assembly and stereo sound we can easily find 60 tracks for mounting environments an action scene. Of course it's better than leftover sounds and not missing. Anyway you can eliminate undesirable in premixes and is worth having different proposals to present to the principal.
The stereo sound editing requires a specific technological environment. On the one hand, readers from which we will take the sounds (1 / 4 ", DAT, CD, Optical Disks) and nonlinear system based on hard drives (ProTools, Sonic Solutions, AKAY DD 1500 and others). From Furthermore, a system of monitoring quality and standards in accordance with multichannel stereo, either Dolby SR (4 channels), 5.1: DTS and Dolby Digital (6 channels) or SDDS (8 channels).
Monitoring a stereophonic sound based on simulation to be used in the room, it helps to reflect on the spatialization and the location of point and environmental sound sources.
In the same vein, the use in mounting the virtual console or one or more automated consoles (ex: 2 Yamaha O2R cascade) allows produce premixes that way to mock give us an idea of the relevance of certain sounds in correlation with each other and with these dialogues.
This process would be completed ideally with a video projection, at least in medium screen, with the help of a good video projector.
Nonlinear systems also offer us the opportunity to dream before quickly move a track, bend, filter and overall process it easily creating a universe of possibilities of sound treatment.
Gone are the days when the mixture was precariously on video (2 or 3 tracks) or even perforated film with magnetic readers. With hard drives based systems we have access to all tracks in real time, mix and even rearrange late-mounted sounds without disturbing the rest of the assembly.
Two mixing techniques in the world. In USA they cohabit in the same room 3 mixers front of a large console 3 divided into parts. In the center mixer dialogues and sides, the mixer environments and music is located. All participate at the same time but are coordinated by the mixer dialogues, confirming once again the eternal subordination of the environments and music to her older sister: the word. Intelligibility and understanding of spoken so requires.
The European and Latin American style (if there is one) involves the pre-mix of dialogues, environments and music by a single mixer. This process requires several weeks, on average 4 for a full-length film and the participation of a single person who works in direct coordination with the sound editor. It is a less divided work than in the USA In addition to the image editor, the sound is necessarily in the mix (at least in France).
It is in the mix where it finally decides the operation of the stereophonic as a narrative, realistic or abstract action: scene in a room without external visual reference but recreation of outdoor environments for stereo; use of channels suround (Subsequent environmental) for vehicular effects "out of frame"; or simply gorgeous outside people or landscapes supported environments typical stereophonic place.
Stereo and technical
There is a great technical challenge as to the correct stereophonic restitution in room. Must strictly comply with the conditions of maintenance and calibration of mixing rooms, as well as ensure monitoring of the process on behalf of a competent technical equipment (eg Dolby Consultant), And of course, the same for the cinemas. As everything can be pink, the viewer should sit on the "ideal chair", ie, in the midline of the room (projection optical axis) and 15 meters (85 dB SPL) screen. That is the place where the mixer sits, and the point where the noise level and spatialization are decided.
The ear becomes more demanding viewers the permanent exhibition to better conditions in film projection and even on TV From the VHS Hi-Fi stereo to DVD, through the conditions of return of a system Home Theater, We could say that the overall quality of sound reproduction has reached very high levels. This demands a constant concern for how we ensure a sound record of incontestable technical quality, without forgetting that the technique is not everything.
Stereophonic somehow destroys the active character of monophonic perception. Imagine where sounds, on the left or right come, makes the viewer more actively involved in the reconstruction of their own sound spaces, constantly imagining. Spacialization stereophonic sets us a unique representation of the sound space, siren left, boys on the right, cars moving from left to right ... Few things are to participate imagining, it seems a little world of radio.
A soulless sound and sense not pass "unnoticed" in the unconscious sense. On the contrary, it will be noted alerting the viewer for its lack of relevance to the narrative.