Architectural acoustics

M. D. Egym, Architectural Acoustics, McGraw-HiU Book Co., Inc., New York, 1988. 

Wi.h the increase in knowledge in the field of acoustics and the awareness of the need for the control of sound, various acoustical products have appeared for employment by the public. This paper covers architectural acoustical materials only. The architectural acoustical products now on the market can be divided into two general classes, the inorganic and the organic type of product. 

FREQUENCY - The number of vibrations, waves, or cycles of any periodic phenomenon per second. In architectural acoustics, the interest lies in the audible frequency range of 20 to 20000 cps Hertz (cycles per second). 

Strong, William J., and George R. Plitnik. Music, Speech, Audio. 3d ed. Provo, Utah Brigham Young University Academic Publishing, 2007. A comprehensive text, written for the layperson, which covers vibration, the ear and hearing, noise, architectural acoustics, speech, musical instruments, and sound recording and reproduction. 

Acoustics architectural acoustics audiology electrical engineering mechanical engineering physics. 

A mean sound reduction index is often indicated which (for sound incidence from all directions) is obtained as the arithmetical mean in the practical range of 100 to 3200 Hz adopted in architectural acoustics. As a rule, it corresponds to insulation at a frequency of 500 Hz. According to DIN 52210, Sheet 4, the adjusted value R should preferably by used as a single-figure rating to indicate the sound reduction. For "single-leaf" partitions, approximately Rw = Rm - 2. 

Complete tables of coefficients of the various materials that nonnally constitute the interior finish of rooms may be found in the various books on architectural acoustics. The following short list will be useful in making simple calculations of the reverberation in rooms. 

Thompson, Emily. The Soundscape of Modernity. Architectural Acoustics and the Culture of Listening in America, 1900-1933. Cambridge mix Press, 2002. 

Other fibrous and porous materials used for sound-absorbing treatments include wood, cellulose, and metal fibers foamed gypsum or Pordand cement combined with other materials and sintered metals. Wood fibers can be combined with binders and dame-retardent chemicals. Metal fibers and sintered metals can be manufactured with finely controlled physical properties. They usually are made for appHcations involving severe chemical or physical environments, although some sintered metal materials have found their way into architectural appHcations. Prior to concerns regarding its carcinogenic properties, asbestos fiber had been used extensively in spray-on acoustical treatments. 

A practical consequence of architecture is to permit acoustical performances to large numbers of listeners by enclosing the sound source within walls. This dramatically increases the sound energy to listeners, particularly those far from the source, relative to free field conditions. A measure of the resulting frequency dependent gain of the room can be obtained from the EDR evaluated at time 0. This frequency response can be considered to be an equalization applied by the room, and is often easily perceived. 

Kahrs, 1988] Kahrs, M. (1988). The architecture of DSP. A DSP multiprocessor. In Proc. IEEEInt. Conf. Acoust., Speech, Signal Processing, pages 2552-2555. 

R. Blum Acoustics and heat transfer in textile architecture, Vortrag Tec/irexri/ 2003, Frankfurt... 

Several sintered glass and glass-ceramic matrix composites obtained from recycled silicate waste have been reported in the literature [100-106]. These are dense or porous products with potential application as building, decoration or architectural materials, such as wall partition blocks, pavements, wall and floor tiles, thermal insulation, fire protection elements, roofing granules and acoustic tiles. Other possible uses include abrasive media for blasting and polishing applications. 

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