Computing revision


Sound is stored in the computer by taking samples of the sound wave at regular intervals and converting them into binary numbers(using an analogue to digital converter).The computer can then recreate the sound by reversing the process.

The file size and quality of the sound recording is affected by the sample rate and bit rate.the sample rate refers to the amount of samples taken each second.It is measured in hertz(like the CPU clock speed)

Sample rate

If the sound wave is not sampled at a high enough rate,this can lower the quality of the sound recording,but the file size would be smaller.

If the sound wave is sampled at a higher sampling rate,this will improve the quality of the recording,but the file size will be much larger.

Bit rate

The bit rate refers to the amount of bits used to store the different levels of sound at each sampling interval.The more bits,the greater range of levels that can be distinguished.This also has the affect of increasing the file size if the bit rate is high eg. 16 bit instead of 8 bit.