Quadratic residue diffuser. Here's the "second" refers to the second side, the remainder divided by the number refers to the quality of the natural numbers (except 1 and itself, can not be divisible by the number) after the remainder of remaining 
 . Quadratic residue diffuser is a common RPG fans sound diffuser. RGP is not known, however diffuser quadratic residue diffusers, there is a story: full name of the second residue 
 Quadratic Residue of Prime Numbers, which is a mathematical sequence model, but by the German physicist, acoustics experts, Manf red used research 
 Study the spread of an effective acoustic Reflection Phase Grating (reflection phase grid), which is the origin of the name of RPG's. In 1970, Schroeder accepted 
 Commissioned several studies to be we think Europe of the twenty outstanding concert hall acoustics. When he found the shoe boxes are a popular shape concert hall, also long and narrow rectangular 
 Space, rather than the larger width than the length of space. After the study, found that the shoe box-type space relatively close to the second side wall away from the audience, the audience from the second side wall reached the ears than the sound waves 
 Spread from the ceiling is even faster to reach the ears to listen. Transmitted from the second side wall between two large ears of the sound waves between the two, the sound waves coming from the ceiling between two ears it sounds small, 
 Perhaps for this reason, so that by the shoebox-type space and audience. 
 Certainly, the Concert Hall's acoustic is very complex and can not cover more than simple speculation. In short, Schroeder developed pursuant to the spread of sound the human ear to listen for 
 Be a great help, and in 1975 published quadratic residue diffuser paper, from the interior acoustic space into a new era of treatment. By 1983, the Naval Resear 
 ch Laboratory of specialization serving diffraction physicist Peter D 'A ntonio created the RPG company to begin mass production to more than the number of secondary spread of the sound based on the theory 
 Wave diffusion plate, and extended to the recording studio and sound room, RPG company's products and the diffusion theory of quadratic residue gradually accepted by the public ...... 
 Quadratic residue diffusers: According to its theoretical formula, to lower the center frequency of proliferation, the quadratic residue diffuser each a "grid" will wider and deeper 
 Instead, the higher the center frequency of proliferation, the quadratic residue diffuser each a "grid", the narrower and more shallow. Based on quadratic residue diffuser design principles and long-term 
 Practical experience that, "diffusion" is mainly for the IF above, especially in the high-frequency and high frequency of the "spread" the best, based on this, the diffuser design of the center of the spread of 
 Frequency is 2000hz, 6 个 lattice diffusion plate in the form of a group. According to theoretical calculations, the center frequency of 2000 hz the quadratic residue diffusers, which spread the frequency range up to: 
 1000 hz ~ 10000