الحاكي (الفونوغراف) - الآلات الموسيقية .. الآلات التي نستخدمها كل يوم وكيف تؤدي عملها

Phonograph - Musical instruments .. The instruments we use every day and how they work

Phonograph:

Any musical instrument is nothing but an invention that vibrates the air in a way that makes you hear different sounds. The phonograph cylinder is a disc in which the vibrations are prepared. You can confirm this if you test the holes of the cylinder under a magnifying glass, you will see that these holes are wavy, as you can see in the picture published on the next page.

If you want to know the way in which these wavy holes cause sounds, bring a card and a pin.

Fix the pin in a corner of the card, then place a cylinder on top of the phonograph, and turn the gramophone. Place the pin's point on the cylinder and listen. Here you hear music emanating from the card under the influence of the needle when it rested on the holes of the cylinder. This is because the waves of these holes cause the pin (needle) to vibrate, and these vibrations in turn cause the card to vibrate. The card carries these vibrations and they are released into the air, thus creating the sounds you hear. If you repeat this experiment and use a pin that you hold between your fingers - without using a card - you will hear the same music. But the sound that you hear in this case is much weaker than the sound that you heard in the first case, because the thin pin cannot cause the air to vibrate strongly and loudly like the large card. Therefore, loudspeakers are installed in the phonograph in the same way, and for the same purpose. The loudspeakers in some of these machines (phonographs) are in the form of a horn, and this horn is a hollow tube inside the phonograph box itself. The amplification of the vibrations occurs in most of these devices through radio valves and a loudspeaker, just as happens in radios.