The history of Architectural Acoustic design for studio has been changing and moving along with a transition of the recording system and method associated with the development of acoustic instruments.
At the time when we recorded with a one-point microphone, beautiful mixture of music performances were desired in the studio, therefore concerning room sound field, good diffused and homogeneous sound were required for recording. The style of recording has changed to multi-microphone recording with the development of multi-channel console and recorder, and small rooms (booths) are planned additionally for recording sound which is not overlapped by other sounds and well-separated between channels. In result, the composition of studio and the production style of music have changed. Moreover, a dead sound field is preferred subject to processing sound with effector like reverberation equipment and the acoustic design suited to the recording instruments is carried out.
About the control room, after the time we used the acoustic design technique to cover sound power of speakers architecturally, acoustic instrument system enables you to have enough power and wide range frequency characteristic, and higher sound insulation performance and acoustic treatment for low frequency sound are required. Also, in the monitor environment of (5.1ch) surround, architectural acoustic design fitted into format of musical media is needed such as acoustic treatment for multi-speakers.
However, the basic concept of the architectural acoustic design has not changed and it is classified broadly into following three performances.
(1) To secure a stable and enough serenity.
(2) To prevent noise from escaping outside.
(3) To have suitable sound field in room.
(1) means we must cut down background noises by soundproofing/vibration proof design, and muffling design. Moreover, a quieter studio is now needed from increased dynamic range by digital recording. We also need to consider the electric noise caused by the electromagnetic wave and the power supply line.
(2) means design for vibration control and noise reduction to the huge sound such as musical performance sound of drums and bass, the monitoring sound from speakers and especially its low frequency noise and vibration. This is a reversal from (1).
(3) means room acoustic design regarding sound field for recording (studio) and sound reproducing (control room).
Omitting one of these three performances will causes a serious hindrance to the operation in the studio. Picking up from them, we introduce our concept and skill regarding room acoustic design.
The sound check is carried out through monitor speakers in a control room even if the system is fully digitized.
This means the quality of monitor sound field as a reference influences the finishing state of the work.
It goes without saying that a choice of high quality monitor speakers is the best and the acoustic design for control room is also very important to maximize their performance.
Especially, under the surround production environment where many speakers are equipped, considerable tasks have been significantly increasing compared to monitor environment for stereo.
Compared large-sized studio to small (private) studio in the sight of scale, the approach of acoustic design to apply is quite different. Flexibility of layout under architectural constrains, problems to be solved concerned such as Building Standard Law and Fire Defense Law and the conditions regarding the facility design need to be considered totally. In addition, it also depends on the sound engineers' preference and persistence on sound or genre of music made in the studio.
Therefore, we believe it is our engineers'role to share the concept of planning studio and the sound image with our clients to make a skill proposal considering the technical and cost aspect such as characteristic features of the monitor speakers and equipments as well as the perspective of the architecture acoustics, and provide a monitor sound field with good quality and good workability.
For instance, as for the transmission frequency characteristics in low frequency range, we start to examine the fundamental shape of the room (shape of floating sound insulation wall) to avoid a negative impact of the vibration of normal mode which relates to shape of the room and to obtain flat characteristic as much as possible at the mixer's position.
Ultimately, we will propose an optimum plan to create a monitoring environment which has a preferable acoustic characteristic, maximizing the use of computer simulation in consideration of the mixing console and large furniture.
As for the acoustic interior design for the middle and high frequency range, we consider traditional items such as avoidance of primary reflected sound which have strong acoustic energy and reverberation design. In addition, we incorporate points of detail in design such as the design and layout of suitable diffuse reflection sides to target the natural localization of sound image and reverberation feeling, the selection of the finish material considered the sound quality and the setting method of the monitor speakers and the acoustic treatment around them.
Surround system has been spreading in various multi-channel media such as DVD, SACD, and digital broadcasting. ( Technical new No.21: monitoring environment of 5.1ch surround)
Even in recording studio, the surround monitor environment like 5.1ch has been requested commonly. As the playback characteristic of a multi-channel audio, each format is regulated by media and the appropriate monitor environment for it is required in studio. If the end users' playback environment and the production environment in the studio are the same, the intended sound field planned in studio can reproduce ideally, however actually, careful consideration of planning is necessary to maintain the compatibility between the sound fields.
The history of surround started with a film. In a film studio, a diffuse sound environment is mainly selected because it can cover a large audience area to maintain compatibility with film theater's sound field. THX pm3 is a typical example.
Antithetically in a production studio for music and digital TV broadcasting, a direct surround environment compatible with ITU-R BS. 775-1 is commonly used to monitor exhaustive expression for localization of sound image which moves in space.
Furthermore, the request for sound field design of surround monitors considering the layout of a vision equipment such as a monitor TV, projector and screen is the characteristic of surround studio, because the recording and the editing for image contents are the main work compared to pure-audio.
As many speakers are set in the surround monitor environment, we need to design with ample studies of the transmission frequency characteristics and the time alignment from a speaker to mixer of each channel speaker, if not, localization feeling and sense of reality will be lost. Similarly in the 2ch stereo environment, it is important that the sound reproduced from each channel is natural and free of tone coloration. In addition, to create the natural and smooth connection of sound field between each channel and to build a sound field able to catch the image of space such as front and back feeling / depth feeling is very important point to consider and concretize in design because they are related to the interior design and the acoustic treatment around the speakers.
With the control technique in low frequency range related to LFE channel and the know-how to reproduce hard center and phantom center without uncomfortable feeling, we propose and embody our customers' ideal monitor field by achieving the acoustic design including equipments and system arrangement in a broader observing point.
As for the sound field required for a recording studio, it is important to combine the appropriate reverberation fitted to record sound from the acoustic instruments and easy to play for musicians improving performance.
An existing recording studio is fully digitized and the performance for transmission system is greatly improved and homogenized. Therefore, the quality of the sound source recorded in a studio as entrance of sound extremely influences the quality of the musical composition.
As for the acoustic design, we assume the layout of musical instruments in recording and allocate sound absorbing and reflecting surfaces properly based on the concept about acoustic field. Regarding the wide main floor, one way of acoustic design is to uniform the sound field of the whole room by heightening the diffusion and the other way is to divide the floor into two areas, the live areas where the rich sound can be recorded and dead areas where the tight sound can be recorded. These acoustic plans are determined by the music genre to record and the concept of recording.
And the acoustic design for a booth depends on the character of instrument to record. For the booth where sound of drums or electric bass is recorded, high sound insulation performance is required because of its huge sound and comparatively dead finish is selected for the sound field. For a piano booth, the layout placement of the reflecting and absorbing surface considering microphone arrangement is needed as well as good visibility for the music performer to have contact with the conductor. Furthermore, the design to record fresh sound is required in the vocal booth, and the announcer booth of MA studio is designed with a slightly dead sound field compared to a vocal booth for recording clear narration.
However, it is important to make sure that small sound and reverberation of musical sound are not to be buried in indoor noise because the dynamic range of music to record is extremely wide. To be lost among the noise means the lack of musical information. Therefore, the requests of sound isolation for outside noise / vibration and the air conditioning noise are more strict compare to a control room.
Our role is broad from a concept decision keeping the customer in mind, architectural acoustic design, construction, confirmation of acoustic performances by measurement when the work is complete to final sound tuning. However, our consistent conviction is the attitude to listen to the sound with our customer and to finish the sound field which they conceived at the beginning.
For instance, the physical specs such as transmission frequency characteristics and reverberation time are measured and evaluated in relatively easy way. However, the final judge for our work will be done by the ears of our customer, not such physical specs. Certainly, it is important to satisfy the physical specs and it is our responsibility to do acoustic design and acoustic construction in order to ensure the target performance. We are making various attempts to share the image of acoustic field with our customers by presenting computer simulation, previewing sound by simulating actual monitor environment in our listening room before starting the construction site to fulfill the image, and also to do sound measurement and sound tuning at the actual site even in the midst of the work.