Skim137's List: Sound & Visual Research

• In a system later to be dubbed Frippertronics, Eno and Fripp set up two reel-to-reel tape decks that would allow audio elements to be added to a continuing tape loop, building up a dense layer of sound that slowly decayed as it turned around and around the deck's playback head. Fripp later soloed on top of this. No Pussyfooting represents the duo's initial experiments with this system, a side each. "Heavenly Music Corporation" demonstrates the beauty of the setup, with several guitar and synth elements building on top of each other, the music slowly evolving, and Fripp ending the piece with low dive-bombing feedback that swoops over the soundscape, bringing the piece to its conclusion. "Swastika Girls," on the other hand, shows how the system can be abused. With too many disconnected sounds sharing the space, some discordant, some melodic, the resulting work lacks form and structure. Eno and Fripp later refined the system on Evening Star and Eno's solo album Discreet Music. Fripp would take the system and base whole albums and live appearances around it (particularly Let the Power Fall). But it was here on No Pussyfooting where it all started.

• Let the Power Fall is an album of Frippertronics, which to the uninitiated can sound like electrical hum. In reality it's a technique developed with Brian Eno, which allows the guitarist to play against a tape loop of sustained notes. With Frippertronics as his mantra, Robert Fripp creates impressive instrumental structures by building layers of sound atop one another. This sort of ambient music is conducive to a specific frame of mind, but like Eno's Discreet Music it rewards the careful listener.

• Discreet Music is his first full foray into what has become known as ambient music. Using the same system of two reel-to-reel tape recorders as No Pussyfooting and Evening Star, Eno was able to layer simple parts atop one another, resulting in a beautiful piece of music that never really changes but constantly evolves with the addition and decay of different parts.

• Robert Fripp's second team up with Brian Eno was a less harsh, more varied affair, closer to Eno's then-developing idea of ambient music than what had come before in No Pussyfooting. The method used, once again, was the endless decaying tape loop system of Frippertronics but refined with pieces such as "Wind on Water" fading up into an already complex bed of layered synths and treated guitar over which Fripp plays long, languid solos.

• "We see rapid evolution when there's rapid environmental change and the biggest part of our environment is culture, and culture is exploding," says Prof Stearns.

   

  "That's I really think the take-home message of the Framingham study, that we are continuing to evolve, that biology is going to change with the culture and it's just a matter of not being able to see it because we're stuck right in the middle of the process right now."

   

  Technology may have limited the impact of evolutionary forces such as predation and disease, but that does not mean humans have stopped evolving.

   

  Far from it, in a world of globalisation, rapidly advancing medical and genetic science and the increasing power of individuals to determine their own life choices, more powerful forces may come into play.

   

  The direction of our future evolution is likely to be driven as much by us as by nature. It may be less dependent on how the world changes us, but ever more so on our growing ability to change the world.

• the relative duration and pitch of a sound
• A pitched sound itself

• Acoustical engineering
• the science of sound and vibration
• The primary goal of acoustical engineering is the reduction of unwanted sounds
• Applications include the design of noise barriers, sound absorbers, silencers, and buffer zones
• Basic sound wave behaviors include absorption, reverberation, diffraction, and refraction.
• Absorption refers both to the sound that transmits through and the energy that is dissipated by a material.
• Reverberation is the persistence of sound that is caused by repeated boundary reflections after the source of the sound stops
• sound waves also bend around surfaces in the path of the waves.
• This bending is known as diffraction.
• Refraction is another kind of sound wave bending. This type of bending, however, is caused by changes in the medium through which the wave is passing and not the presence of obstacles in the path of a sound wave. Temperature gradients, for example, cause bending in sound waves
• Architectural Acoustics
• this branch of acoustical engineering applies to any enclosed area, whether concert halls, office spaces, or ventilation ducts.
• One thing that can affect speech intelligibility is standing waves.
• The acoustics of rooms are often considered to ensure speech intelligibility and privacy.
• A second potential cause of poor speech intelligibility is reverberation. This effect can be reduced through porous absorbing materials.
• To avoid this, many rooms are designed with angled walls.
• Examples of these include glass or mineral fibers, textiles, and polyurethane cell foams.^[5] Since the absorption of each material is different for different frequencies of sound, the materials used often vary based on the intended purpose of the room, though compound partitions, or layered combinations of different materials, make more effective absorbers.^[
• A third common technique for room acoustics is the use of masking. Masking is the canceling or drowning out of other sounds. Although this raises the overall sound pressure, masking can make irritating noises less distracting and add speech privacy.
• Reducing ventilation noise serves as another example of applied architectural acoustics. Many heating, ventilation, and air conditioning systems have silencers. Silencers can actively cancel noise by electronic feed forward and feedback techniques, or muffle the sound by either having sudden changes in cross section or walls with absorbent linings.
• Environmental Acoustics
• Environmental acoustics are concerned with the control of sound and vibrations in an outdoor environment. This includes sounds generated by traffic, aircraft, industrial equipment, and anything else that might be considered a nuisance or a safety concern.
• An Example of noise barriers are the walls built between highways and residential areas. Barriers are less effective in reducing high frequency noise due to the way sound diffracts around walls, but can reduce the overall loudness of traffic noise by as much as one half.^[
• Environmental noise control often involves the creation of noise barriers and use of buffer zones.

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• Acoustic absorption is that property of any material that changes the acoustic energy of sound waves into another form, often heat, which it to some extent retains, as opposed to that sound energy that material reflects or conducts.
• The absorptive of a given material is frequency-dependent and is affected by size, shape, location and the mounting method used. Porous insulative materials such as mineral wool or glass wool are effective sound absorbers compared with good conductors such as metals. Micro perforated plates, however, supply "hard" absorptive surfaces.

• Micro perforated plate
• A Micro Perforated Plate (MPP) is a device used to absorb sound, reducing its intensity. It consists of a thin flat plate, made from one of several different materials, with small holes punched in it. An MPP offers an alternative to traditional sound absorbers made from porous materials.

• The goal of a sound absorber is to convert acoustical energy into heat. In a traditional absorber, the sound wave propagates into the absorber. Because of the proximity of the porous material, the oscillating air molecules inside the absorber lose their acoustical energy due to friction.

   

  A MPP works in almost the same way. When the oscillating air molecules penetrate the MPP, the friction between the air in motion and the surface of the MPP dissipates the acoustical energy.

• Traditional sound absorbers are porous materials such as mineral wool, glass or polyester fibres. It is not possible to use these materials in harsh environments such as engine compartments. Traditional absorbers have many drawbacks, including pollution, the risk of fire, and problems with the useful lifetime of the absorbing material.

   

  The main reason why Micro Perforates have become so popular among acousticians is that they have a good absorption performance but without the disadvantages of a porous material. Furthermore, an MPP is also preferable from an aesthetic point of view.

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• The focal point of the whole system is the blade named RICCIO ©, an innovative technological system that transform the air movement into energy and then, thanks to a generator, into electricity.

  During the vehicle transit close by the noise barrier it produces a pressure wave with a kinetic energy and potential. This energy is transferred to the blade orthogonally to the wave front. Then the blade stimulated by the wave, begins swinging in analogy to a damped harmonic oscillator.

  The electricity produced will be stored by appropriate capacitors. The electricity will be used to manage the noise barriers and to provide clean energy for the districts.

• Solar Animal Repeller with Motion Detector