4 - Áudio (noções básicas de som): Parte 1

Olá e bem vindo.

As informações desta página foram transferidas e atualizadas na página Curso de treinamento: Áudio (Noções básicas de som): Parte 1

Sound is all around us. We don’t need any particular talent to use it. Doctors tell us that we can hear sounds in the womb.

Usar bem o som é uma história diferente. Ser capaz de julgar o som, saber se é o melhor possível para seus clientes - ou pelo menos aceitável - é outra história.

For a simple definition, “Sound” is what we hear. But actually every sound involves hundreds of steps. These steps begin with a motion that takes place at one point. The drummer hits the drum, and it vibrates, the bell gets hit and it vibrates, we push air up our throats and make it vibrate.

We can’t see it, but you can visualize it by thinking about it like a pebble that is thrown into a pond.

Muito rapidamente, aquele movimento inicia uma série de movimentos que se espalham como ondas. Como a onda circular na água, o som é uma onda que se espalha a partir da fonte.

No entanto, existem algumas diferenças com a comparação da água. A primeira é que vemos a superfície do lago como uma superfície plana. Nossa onda sonora é diferente - sai em todas as direções de um alto-falante. É semelhante à forma como a luz sai de uma chama - da parte superior e inferior e de todos os lados ao mesmo tempo, de todos os ângulos para todos os cantos. A segunda diferença é que a onda que se espalha, a energia que se espalha pelo alto-falante, está impulsionando o ar. O ar age de maneira diferente da água.

But the main thing is true – a wave of sound and a wave on water and a wave of light all carry energy.

Eventualmente, a energia da onda chega aos nossos ouvidos. Em seguida, vai para dentro dos ouvidos e, finalmente (por meio de um processo que é tão sofisticado que parece que deve ser mágico), o movimento das ondas se transforma em eletricidade. Essa energia desce alguns nervos. Essa nova onda de energia elétrica transmite o que ouvimos, esse movimento original, ao cérebro para análise.

Sometimes the word Sound and the word “Audio” seem like they mean the same thing. But they can be different. We will say that “audio” is a type of sound that is being played through some equipment. This is the sound that we hear in the movie auditorium.

Grammar in English is complicated though, so it is not always true. We will say that the sound of his voice onscreen was pleasant – we won’t say, the ‘audio’ of his voice. And, we won’t say that the voice of the singer on the street had amazing ‘audio’. Instead, we would say that the ‘sound’ of his or her voice was amazing.

Whether the sound is natural or reproduced, the path to our ears is complex. You don’t need to know about most of that complexity, just like we don’t need to know about most of the complexity of the sound speaker on the wall.

But as a professional-in-training, you should understand enough so that you aren’t fooled by something that isn’t immediately obvious. You should be able to respond correctly if an audience member says something about the sound. For example, you could ask a appropriate question that will give the tech who will repair the problem better information.

Because your job is to tell the technician about negative changes in the sound – a rattle, a hum, no sound, distorted sound, sound that isn’t balanced (too much or too little from one side, for example)…and where…and if possible, why.

So, we’ll start slow. We’ll cover some basics. And after you hear a test DCP (See: O que significa: DCP) in an auditorium a few times – or 10 or 20 times – you can review the material here to refine your knowledge. Perhaps you will find questions while you work that were presented already, but didn’t seem important before you refined your ability to notice things. When we do this, we are learning to evaluate by significance.

And, you can ask questions. Because no one was born with this data, everyone had to learn this. Much of it is new, and all of it has been refined very recently as science and technology has progressed.

O sistema de áudio do auditório
O Sistema de Áudio Auditório, do sistema de biblioteca aos alto-falantes - Ignore as partes sob as caixas roxas.

The Audio portion of a movie comes out of many speakers around the auditorium.

Most of the time there are 3 speakers behind the screen called Left Front (LF), Center Front (CF) and Right Front (RF). Usually those speakers are spread out across the screen, closer to the top than across the middle, and pointed slightly downward toward the center of the room. On the side walls, and the back walls, are the Left Surround and the Right Surround speakers.

Finally, there is a speaker (or set of speakers) that handle the extreme low frequencies. These are called the Low Frequency Effect speakers, and abbreviated, LFE.

Those 6 sets of speakers (around the room in a circle, LF, CF, RF, RSurr, LSurr and LFE) are called a 5.1 system.

There is a variation of the 5.1 system called the 7.1 system. The difference between 5.1 and 7.1 is simple – the speakers on the rear wall in a 7.1 system have a separate amplifier system for those right and left rear speakers (instead of being part of the Left Surround and Right Surround systems.)

In those simple statements there is a lot of unsaid information.

For example, when the word speaker is used, it probably means a box, or even two or three boxes. Each box might have 1 or 2 or 3 speakers in them. Why are there different designs?

The first answer is that common situation: Compromise. The movie shows different kinds of scenes. Big open spaces, small tight spaces. Places without echo, places with an echo when people talk. We don’t think about it, but we would notice that a room sounds weird if it had no echo. A movie theater has to make both those kinds of sounds, and many others. Loud, soft, surprising loud~! Conversation and war sounds. Crying during war sounds.

It is all very difficult to do, and each size of auditorium is different. The seats can affect the sound, the number of people wearing heavy jackets make the sound act differently.

Before we go onto Part 2 of Audio Basics (Sound), take a break from study for a week. Become aware of your perception of sounds. Listen to the background sounds. Listen for the difference between sounds that bother you and sounds that are pleasing.

Remember that they are all waves, coming from a source, and that some of those waves are coming directly and some are bouncing off of walls and ceilings – but our ears and brain put them all together naturally.

Good luck and have fun.