Anadolu Üniversitesi İletişim Bilimleri Fakültesi televizyon stüdyosu akustik performansının değerlendirilmesi /
Yazar: DENİZ SİPAHİOĞLU
Danışman: DOÇ. DR. SEVTAP DEMİRKALE YILMAZ
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü
Derece: Yüksek Lisans, 1995
Konu: Mimarlık = Architecture
Dizin: Akustik = Acoustic ; Anadolu Üniversitesi İletişim Fakültesi = Anatolian University Communication Faculty ; Televizyon stüdyosu = Television studio

Özet:
ÖZET Stüdyolar için akustik performans sesli filmlerin ortaya çıkmasıyla önem kazanmış, sinema filmlerine sesin eklenmesi, insanları filmlerin çekildiği stüdyoların akustik performansı üzerinde düşünmeye zorlamıştır. Dünyada TV yayıncılığının başlayıp hızla ilerlemesi sonucu, stüdyoların akustik performansına ilişkin deneysel ve teorik çalışmalar da hızlanmıştır. Diğer kapalı hacimlerdeki alıcı insan kulağının yerine, stüdyolarda insan kulağına göre çok daha hassas olan mikrofonların alması ve mikrofonların stüdyolardaki akustik kusurları ve eksiklikleri açıkça belirleyerek dinleyicilerde tatminsizlik yaratması, stüdyo tasarımlarına titizlikle yaklaşılmasını zorunlu kılmıştır. Yukarda özetlenen TV stüdyolarının akustik tasarım açısından gelişimi doğrultusunda gerçekleştirilen bu tez, Anadolu Üniversitesi İletişim Bilimleri Fakültesi televizyon stüdyosunun, hacim akustiği kriterleri açısından performansını değerlendiren bir çalışmadır. Çalışmayla günümüzde etkinliği giderek artan kitle iletişim araçlarından televizyonların programlarının yapıldığı yer olan televizyon stüdyolarının hacim akustiği kriterlerinin belirlenmesi amaçlanmış; stüdyoların akustik kusurlarının giderilmesi, stüdyoların akustik performansını doğrudan etkileyebilen mobilya ve dekorasyon malzemeleri ile teknik servislerinin incelenmesi, stüdyoları destekleyen birimler olan kontrol odalarının değerlendirilmesi gerçekleştirilmiştir. Konuyla ilgili teorik çalışmalar aktarıldıktan sonra Anadolu Üniversitesi İletişim Bilimleri Fakültesi televizyon stüdyosunun, hacim akustiği özellikleri; teorik açıdan; istatistiksel teori kapsamına giren analizler ve dalga teorisi kapsamına giren analizler yoluyla iki aşamalı olarak değerlendirilmiştir. Bunların dışında, sübjektif bir değerlendirme kriteri olarak, stüdyoda çalışanlarla görüşmeler yapılmıştır. X

Abstract:
SUMMARY in this thesis, Mass Communication Faculty television studio of Anadolu University is being evaluated according to its room acoustic properties. in the fırst three chapters, the definitions about the subject and the theoretical techniqu.es that has been developed are being simply described. The properties of sound, and its behaviors in enclosed spaces are being described in the second chapter. The first section of the second chapter is about the definitions essential for understanding the follovving chapters. The word sound has two definitions: 1)Physically speaking, it is a fluctuation in pressure, a partide displacement in an elastic medium, like air. This is objective sound. 2)Physiologically it is an auditory sensation evoked by the physical fluctuation described above. This is subjective sound. The number of displacements ör oscillations that a partide under goes in l second is called frequency. The unit of the frequency is Hertz (Hz). The standard frequencies selected arbitrarily as representative of significance in environmental acoustic are 63, 125,250, 500, 1000,2000, 4000, 8000 The distance a sound wave travels during each complete cycle of vibration, that is, the distance between the layers of compression, is called wavelength. Wavelength of sound vvithin the frequency range of 20 to 1000 Hz extends from 17m to 25mm. The consideration of the relationship between xifrequencies and wavelengths is important in the acoustical design of auditoriums. The second section of the second chapter describes the behaviour of sound in enclosed spaces. Those are; reflection, absorption, diffusion, refiection, reverberation and room resonance. in the first section of the third chapter, generally TV studios, in the second section of the third cahpter, acoustical requirements for TV studios and elimination of acoustical defects such as: Echoe, flutter echoe. focusing, room rezonance and noise, are briefly described. The TV studios should have to met, acoustical requirements for rooms and must provide high degree of isolation against extraneous noise and vibration. Particular attention must be given to the following requirements in their design. 1)An optimum size and shape for the studio must be established. 2)A high degree of diffusion must be secured. 3)ideal reverberation characteristics must be provided 4)Acoustical defects must be totally prevented. 5)Noises and vibrations must be completely eliminated. The size of a studio is determined by the physical space required for its occupants, equipment and furniture, by the function for which the room is to be used, and by the acoustical requirements. There are no room proportions that are universally ör unanimously recommended as optimum. For rectangular studios room proportions, 1:1.25:1.60, 1:1.50:2.50 and 1:2.50:3.20 are generally advocated. it must be stressed that the significance of room proportions in studio acoustics diminishes when. The studio has a non rectanguler floor, xii. Ideal reverberation characteristics have been achieved,. Acoustical finishes, particularly those with efficient low-frequency absorption, are generously used and evenly distributed,. A high degree of diffusion has been provided,. The volume of the studio is above 7 1 0 cum. Television studios are constructed in different sizes, according to the required floor area and height. There are four main types: l)Audience studios with permanent audience seating.Their area may be as large as 1400 square meter and their volume about 14200 cubic meter. 2)General-purpose studios, for all types of programs. 3)Small interview and announce studios. 4)Dubbing suites. A considerable clear height is usually required over the working area of the larger studios to accommodate the lighting grid, with its systemof catwalks, and for flying the scenery. The first and the second section of the fourth chapter, expresses the effects of the studio furniture and decoration of the TV studios, to its acoustic quality. Whilst certain items of furniture or fittings such as acoustic screens, tables, curtains and carpets are specified to produce particular effects. It is important to remember that anything in the studio will by its very presence, affect the overall acoustics in some way. Waste paper bins, metal tape bins and filing cabinets, should all be sited ouside studio areas. In the third section of the fourth chapter control rooms and their layouts are described. XlllThe aim of control room design is to provide a sound that is affected as little as possible by the room. In areas where stereo sound is dealt with, the monitoring environment should also give the operator good information and image positioning. Unfortunately, control rooms contain acoustically reflective items such as control desks and observation windows, usually with a lot of additional technical equipment. These not only have undesirable acoustic qualities in themselves, but also restrict the places where acoustic treatment can be positioned on the walls. To get the best comprimise in the acoustic design, it is especially important that the acoustics consultant is kept fully involved with the equipment layout and that no constructional changes are made without consultation. The first section of the fifth chapter describes the theoretical studies, including descriptions essential for calculations, and the two methods of calculating reverberation time; Sabine and Eyring. The first section of the fifth chapter ended with comparing the methods. The second section of the fifth chapter is about geometrical analysis of the rooms. The fifth chapter is ended with desribing the wave theory of enclosed spaces. Also, calculation of the normal modes of the room is determined in this section. In the sixth chapter, the acoustical evaluation of the mass communication faculty TV studio of Anadolu University is carried out, related to the basic knowledge given in the previous chapters. In the evaluation of the TV studio, the numerical and physical attributes of the studio is given by using tables and figures. A rigorous approach called physical acoustics is used to determine the reverberation characteristics of the studio by using both Sabine and Eyring formulaes. The existing reverberation time is calculated in the frequency range 125 to 4000 Hz. The sound absorption coefficients of the materials used in the TV studio, are chosen from the tables in the acoustical literature. Surfaces which covers a great area in the studio are taken with diffarent alternative coefficients for each. While selecting the coefficients from literature a HVparticular attention is given to the similarities, between the materials used in the hail and described in the literatüre. As a second method of evaluating the TV studio, wave theory of the soımd is used. By using this theory, the normal modes of the room is calculated with formulaes determined in the previous section. The result as described for the mass communication TV studio of Anadolu University is not sufficient in acoustical performance. Since the reverberation characteristics of the TV studios, used for talk programs, recommended a flat curve, the evaluated TV studio RT characteristics does not have a flat curve. Also the natural resonance occurring at coincident frequencies will cause coloration of the sound, because of the square shape of the room. The proportions of the room are not suitable for TV studios. Finally, the sizes of the studios and absorptive treatments that will be used in the studios are very important in the design and the construction of the studios. Also another important subject is to use the same details and same acoustical treatments in the projects at construction. A full acoustic survey of the acoustics, Sound insulation and Noise levels should be carried out at the completion of ali building work with the technical equipment in position, to confirm that the necessary acoustic standarts, as specifıed in the original project requirements, have been met ör whether modifıcations ör remedial work will be required.