Category Science

Why is it said that the telephone is the end result of many other inventions?

             The telephone that we see around today was certainly not the first model developed for communication. Prior to its invention, many people had attempted to make different types of phones. However, Graham Bell’s telephone, invented in 1876 was the most successful.

             Most of the earliest models were mechanical acoustic devices that transmitted speech over a distance greater than that of normal speech.

             One important discovery during the 17th century was by Robert Hooke. He made an acoustic string phone in 1667. By the 19th century, various types of telegraphs were developed. It was after improvements of the electrical telegraph that the telephone emerged.

             There were many people who worked on this invention. However, it was Alexander Graham Bell, who won the patent for the device. 

What is meant by sound recording?

          Sound recording and reproduction refers to the inscription and re-creation of sound waves, such as spoken voice, singing, instrumental music, or sound effects.

          The inscription could be electrical, mechanical, electronic or digital in nature. The earliest method of music reproduction was done through mechanical systems.

          Today, there are two main classes of sound recording technology – analogue recording and digital recording.

               Acoustic analogue recording is done with the help of a microphone diaphragm that can detect and sense the changes in atmospheric pressure caused by acoustic sound waves. It then records the waves as a mechanical representation on a medium such as a phonograph record.

              In digital recordings, analogue signals picked by a microphone are converted to a digital form by a process called digitization.

              The first all-digitally-recorded popular music album, Ry Cooder’s ‘Bop till You Drop’ was released in 1979. 

Why is the introduction of the phonautograph a turning point?

            The phonautograph was perhaps the first device in history that could record sounds. It was patented by French inventor Edouard-Leon Scott de Martinville in 1857.

            Phonautograms or phonautograph recordings made in 1857 were the earliest known recordings of the human voice. They consisted of sheets of paper with sound-wave-modulated white lines created by a vibrating stylus that cut through a coating of soot as the paper passed under it. That means the recordings were visual representations of the sound.

           The earliest known recording of intelligible spoken words is the phonautogram containing the opening lines of Torquato Tasso’s pastoral drama ‘Aminta’. It is believed to have been recorded in April or May, 1860.

           Luckily, a few recordings have been recovered over the past few years. The phonautogram of Au Clair de la Lune, a French folk song made in 1860 was played as sound for the first time in 2008. 

Why is the phonograph an important invention?

          Invented in 1877 by Thomas Edison, the phonograph was a device meant for the mechanical recording and reproduction of sound.

          The significance of this device was that it was the first to reproduce a recorded sound. Till then, other inventors had produced devices that could only record sounds.

          Edison’s phonograph originally recorded sound on to a tinfoil sheet wrapped around a rotating cylinder. He patented it in 1878. The invention became popular across the globe very soon. Over the next two decades, the commercial recording, distribution, and sale of sound recordings became a new international industry.

          The next important invention was the gramophone disc. The waveform of sound vibrations were recorded as corresponding physical deviations of a spiral groove engraved into the surface of a rotating cylinder called the ‘record’.

          To recreate the sound, the surface was similarly rotated. Then, the playback stylus would trace the groove, and start vibrating. As a result, the recorded sound would be faintly reproduced. 

How do human beings make sound?

               From the very moment of birth, we, humans are capable of making sounds. First in the form of cries, then as incomplete words, and finally, as clear speech. There are many parts in our body that help us speak, or produce sounds.

              One of the main parts is the voice box, or larynx. It is a lump that remains close to our throat, and has two vocal cords stretching across it. They are the source for speech production in our body. That is, when air is exhaled from the lungs, it causes the vibration of the vocal cords. This in turn results in the production of sounds.

               However, there are other parts as well, that help in the process. The mouth and the nostrils are two of them. Yet another organ is the tongue. It plays a vital role in speech by moving into different shapes. Then there are the lips and the teeth, which help in the better expression of sounds. 

Why is it said that the ear plays a wonderful role in receiving sounds?

            The human ear is a wonderful organ that performs some of the most important functions in the body. It detects and analyzes sounds, and also maintains the sense of balance.

            Structurally, the external ear is created in a peculiar way. It has many twists and folds that help in enhancing certain sounds up to 100 times.

            Designed in a way as to make the skin maintain its funnel shape, a healthy ear enables the capturing of even the tiniest vibration.

            In addition, the ear can help determine sound direction. It can also decide the range of sounds we hear. However, as we grow old, we become less sensitive to sounds, and may not be able to hear high pitched sounds like the squeaking of a bat. But this could be picked up by a child. It has been found that a normal human can detect frequencies between 20 Hz and 20 kHz.