Term 2- Sampling Rate

Yes Term 2 already! Term 1 went so fast and i bet Term 2 is going to go faster. Today is Period 1 and what a better way to start the term then with IST first period. Yes todays Lesson Mr. Lennon told us stuff about sounds and Sampling. He told us about bits and how many bits make up a byte. At the moment I am confused about this, and not just me but my fellow classmates do not understand the physical component of this topic. Therefore Sir has given us some questions to complete. So our knowledge can vary and we might understand it. Before I complete the questions Sir told us to listen to some sounds ono wikipedia and this will show how bits can make a difference in the sound. Like in example:


HERE are the sounds listed from best to worst-

Firstly I tried the best sound and i realised that it was so clear and so good, I could here everything perfectly.
Then I heard the last sound, and realised that i couldnt understand what the person was saying because the sound quanlity was so poor. Even when i listened it at home it was so poor, and when i clicked on the link it took me to the windows media player, you may know that whenever you play something on widows media player, when it hears sound colourful lines spread the page , telling us the wave length.So when I put it the good quanlity one the waves were so clear and nicely curved, but when i pressed the poor one, its waves were really blury and not curved at all.



Questions:

1. Sound moves through what medium?

We hear sounds because our ears are sensitive to these pressure waves.

2.   What unit is used to measure sample size?
Essentially this is the number of digits in the digital representation of each sample. Think of the sample rate as the horizontal precision of the digital waveform, and the sample format as the vertical precision. An audio CD has a precision of 16 bits, which corresponds to about 5 decimal digits. Therefore it is measured in bits.

3.  What unit is used to measure sampling rate?

The rate at which the samples are captured or played back, measured in Hertz (Hz)

4.  Compare the quality of AM, FM and Digital radio.
AM:
Sending pure digital data through the approximately 20 kilohertz AM channel is roughly equivalent to sending data through two 33 kbit/s analog telephone lines, thus limiting the maximum throughput possible
FM:
The FM hybrid digital/analog mode offers four options which can carry approximately 100, 112, 125, or 150 kbit/s of lossy data depending upon the station manager's power budget and/or desired range of signal. The HD Radio also provides several pure digital modes with up to 300 kbit/s bitrate, and enabling extra features like surround sound. Like AM, pure digital FM provides a "fallback" condition where it reverts to a more-robust 25 kbit/s signal.
DIGITAL RADIO:
 Today the most common meaning is digital radio broadcasting technologies, such as the digital audio broadcasting (DAB) system, also known as Eureka 147. In these systems, the analog audio signal is digitized into zeros and ones, compressed using formats such as mp2, and transmitted using a digital modulation scheme. The aim is to increase the number of radio programs in a given spectrum, to improve the audio quality, to eliminate fading problems in mobile environments, to allow additional datacasting services, and to decrease the transmission power or the number of transmitters required to cover a region. However, analog radio programs and equipment, especially for the FM broadcasting system, still dominate the market.