Acoustics




 * In the two principal videos is explains that the sound is produced by an impact to any body, which emits vibrations. Music, for example, arises through the impact that the musician does on the instruments, to create different types of tunes, so it is important that the force used on the object must be the adequate. The material of the instrument is also relevant because the sound will be not similar in electric guitar strings as in the bass, will be not similar the sound emitted by a drum to the sound emitted by a djembe (although belonging to the same family of instruments). Then, the sound depends on an impact, the force used and the material of the object. **

Speed: The speed of sound is the distance travelled during a unit of time by a sound wave propagating through an elastic medium.

Frequency: Number of waves that pass a fixed point per unit time; also, the number of cycles or vibrations undergone in unit time by a body in periodic motion. Frequency is the reciprocal of the time taken to complete one cycle (the period). Frequency is usually expressed in units called hertz (Hz).

Wavelength: is the spatial period of the wave, the distance over which the wave's shape repeats. It is usually  determined by considering the distance between consecutive corresponding points of the same phase, such as crests, troughs, or zero crossings, and is a characteristic of both traveling waves and standing waves, as well as other spatial wave patterns.

Longitudinal Waves: also known as "l-waves", are waves that have the same direction of vibration as their direction of travel, which means that the movement of the medium is in the same direction as or the opposite direction to the motion of the wave. Mechanical longitudinal waves have been also referred to as compressional waves or compression waves.

Transverse Wave: Is a moving wave that consists of oscillations occurring  perpendicular (or right angled) to the direction of energy transfer. If a transverse wave is moving in the positive x-direction, its oscillations are in up and down directions that lie in the y–z plane.

Speed = distance travelled in unit time (m/s) Frequency = number of complete cycles in one second (Hz) Wavelength = distance between matching points on the wave (m) Longitudinal = vibration parallel to direction of travel of wave Transverse = vibration at right angle to direction of travel of wave

__Notes of the Videos: __ //In the two principal videos is explains that the sound is produced by an impact to any body, which emits vibrations. Music, for example, arises through the impact that the musician does on the instruments, to create different types of tunes, so it is important that the force used on the object must be the adequate. The material of the instrument is also relevant because the sound will be not similar in electric guitar strings as in the bass, will be not similar the sound emitted by a drum to the sound emitted by a djembe (although belonging to the same family of instruments). Then, the sound depends on an impact, the force used and the material of the object. //

__<span style="color: #ffcc00; font-family: 'Arial Black',Gadget,sans-serif; font-size: 110%;">Notes of the Web-Sites __ //<span style="color: #ff7c00; font-family: 'Arial Black',Gadget,sans-serif; font-size: 110%;">Room Acoustic // <span style="font-family: Arial,Verdana,Tahoma,Helvetica;"> <span style="color: #ffcc00; font-family: 'Arial Black',Gadget,sans-serif; font-size: 14px; line-height: 21px;">Room acoustic descriptors <span style="background-color: #ffffff; font-family: 'Arial Black',Gadget,sans-serif; font-size: 95%;">Different room acoustic descriptors correspond to different sound attributes. These attributes can be described as reverberance, clarity, auditory strength and spatial decay. In the world of acoustics there are descriptors that quantify these attributes.

<span style="background-color: #ffffff; color: #a7a7a7; display: block; font-family: arial,helvetica,sans-serif,Verdana,Tahoma,Helvetica; font-size: 16px; text-align: left;"> <span style="background-color: #ffffff; color: #a7a7a7; display: block; font-family: arial,helvetica,sans-serif,Verdana,Tahoma,Helvetica; font-size: 16px; text-align: left;"> <span style="background-color: #ffffff; color: #a7a7a7; display: block; font-family: arial,helvetica,sans-serif,Verdana,Tahoma,Helvetica; font-size: 16px; text-align: left;"> <span style="background-color: #ffffff; color: #a7a7a7; display: block; font-family: arial,helvetica,sans-serif,Verdana,Tahoma,Helvetica; font-size: 16px; text-align: left;"> <span style="background-color: #ffffff; color: #ffcc00; font-family: 'Arial Black',Gadget,sans-serif; font-size: 14px;">Make the right room acoustic demands from the start <span style="background-color: #ffffff; color: #000000; font-family: 'Arial Black',Gadget,sans-serif; font-size: 9pt;">It is vital to clearly specify your requirements for room acoustic quality early on in the building process.

//<span style="color: #ff7c00; font-family: 'Arial Black',Gadget,sans-serif; font-size: 110%;">Acoustic Design // <span style="font-family: 'Arial Black',Gadget,sans-serif;">Room acoustic design can make people feel better, work better and heal better. The third illustrates how the sound environment can affect people throughout their lives.

<span style="background-color: #ffffff; display: block; font-family: arial,helvetica,sans-serif,Verdana,Tahoma,Helvetica; text-align: left;"> <span style="background-color: #ffffff; display: block; font-family: arial,helvetica,sans-serif,Verdana,Tahoma,Helvetica; text-align: left;"> The first is a room with little sound absorption, a “hard room” in which the surfaces reflect most of the noise.
 * [[image:http://www.ecophon.com/Templates/Ecophon/Handlers/IR.ashx?T=TL&P=/Global/07.Illustrations%20-%20Descriptive/Room%20Acoustic%20Comfort/room_acoustic_comfort.jpg&PI=10370&PL=en]] || <span style="color: #ffcc00; display: block; font-family: 'Arial Black',Gadget,sans-serif; font-size: 14px; text-align: left;">Different acoustic room types <span style="font-family: 'Arial Black',Gadget,sans-serif;">The way sound behaves and affect the people in the room depends heavily on the room geometrie and placement of absorption material. ||

<span style="font-family: 'Arial Black',Gadget,sans-serif;">Using absoprtion class A means that less material is needed and quality of teaching, working and healing is optimised. || <span style="background-color: #ffffff; display: block; font-family: arial,helvetica,sans-serif,Verdana,Tahoma,Helvetica; text-align: left;">
 * [[image:http://www.ecophon.com/Templates/Ecophon/Handlers/IR.ashx?T=TL&P=/Global/07.Illustrations%20-%20Descriptive/Room%20Acoustic%20Comfort/sound_energy.jpg&PI=10337&PL=en align="center"]] || <span style="color: #ffcc00; display: block; font-family: 'Arial Black',Gadget,sans-serif; font-size: 14px; text-align: left;">Chossing the right sound absorption
 * [[image:http://www.ecophon.com/Templates/Ecophon/Handlers/IR.ashx?T=TL&P=/Global/14.Concept%20Development/01.Office/Flash/Corridor-01.jpg&PI=10369&PL=en]] || <span style="background-color: #ffffff; color: #ffcc00; display: block; font-family: 'Arial Black',Gadget,sans-serif; font-size: 14px; text-align: left;">Acoustic design with wall panels and acoustical island <span style="font-family: 'Arial Black',Gadget,sans-serif;">A fully covered absorbing ceiling is the preferred solution for placement of sound absorption material. Sometimes, the design might require additional or alternative solutions. ||