Sound

Sound

1. Analogue Sound

   • It is constantly recorded with no breaks. It provides a crisp and clear sound quality.

2. Digital Sound

   • This is recorded digitally using an analogue to digital converter (ADC)

3. Quantisation

   • It is the name of the audio snapshot when it has to be rounded off to the nearest available digital value.

4. Sampling rate

   • The amount of times a sound is recorded per second. It is usually measured in hertz or kilohertz. e.g. 44.1 kHz is equal to 44, 100 samples of audio recorded every second.

5. Sample resolution

   • This refers to how many different values the samples can take on. The higher the sample resolution, the more accurate the representation of the level of each sample. Digital audio is normally found in one of two resolutions, 8 bit and 16 bit. 16 bit is much clearer, consisting of more different values than the human ear cfan distinguish.

6. Bit rate

   • Bit rate is the number of bits per second. It is the amount of sound information presented to the listener every second.
   • Bit rate=bitspersample x samplespersecond x number of channels
   • file size= (bitspersample x samplespersecond x channels x duration)/8

7. Bit depth

   • The number of bits used to describe each sample.

8. Modulation

   • Alteration of the amplitude or frequency of an electromagnetic wave or other oscillation in accordance with the variations of a second signal.

9. File size

   • File size (bits)= rate x res x secs = sampling rate
     • where res = sample resolution and secs= number of secs