BISOPE series 57 decibel; DB dB, a way to express the level of noise an...

BISOPE series 57- decibel; DB (dB, a way to express the level of noise and vibration)

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In engineering - generally, the unit of ‘dB (decibel; dB)’ is used to express the ‘size’ of noise, vibration, electricity, etc. If this value is large, it means that the value of noise and vibration is large. Why were these units created? You can just call them pressure (pa), acceleration (G), and voltage (V) as they are... The reason is that the unit dB easily represents the 'range of change in sensation.' So, strictly speaking, dB cannot be said to be a unit because it is a value that varies depending on how the standard is set.

 

Weber-Fechner's law

 

The change in human sensory quantity (P) can be best expressed as the ratio of the change amount to the reference stimulation quantity (S).

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BISOPE series 44 Point, Line, and Planesquare sound sources distance at...

BISOPE series 44- Point, Line, and Plane(square) sound sources (distance attenuation)

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A sound source is a source that generates sound power. If sound sources are classified in the form of poles, they can be classified into monopole, dipole, and quadrupole sound sources. Among them, a point source is a source that is radiated forming a spherical wave from a small sphere that periodically expands and contracts as a result of a change in volume, and is also called a monopole source. In addition, when countless point sources form a straight line, this form like a train is called a line source.

The power radiated from the sound source decreases linearly in the area that can be assumed to be a free sound field (an area that is not very close to the sound source and the sound pressure decreases uniformly as the distance increases). '. In other words, the farther the distance, the quieter the sound. However, the attenuation ratio of the sound power according to the distance is different depending on the shape of the sound source. That is, points decay quickly and lines decay slowly. explain this

 

distance attenuation according to the sound source

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point, line and plane are explained by speaker, train and wall.

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BISOPE series 43- What does solid sound(Structure borne noise) mean?

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The sound of bands and orchestras resounding in the concert hall entertains our brains. Unfortunately, we also analyze the sound. A string instrument that produces sound by plucking the string and its harmonics, a wind instrument that blows wind and produces a beautiful sound with the pipe's unique frequency, and a drum of its own size by beating a drum A percussion instrument that makes a percussive sound, and a keyboard instrument, a person's vocal cords vibrate, and a person's vocal cords vibrate in the throat... This is just music, but it is also called 'structure borne noise, air borne noise' in engineering. What does that mean? is it a guitar? is it a flute? is it a piano? Is it the sound of drums? Why are the pictures of railroad rails and wheels below?

 

The difference between 'structure borne noise, air borne noise'

 

1. What is the difference between the sound coming out of a speaker or mouth and 2. the sound made when hitting a xylophone or drum?

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All copyright  korea CBM  written by BISOPE ,  www.kCBM.kr

 

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