representing audio

• analogue data is a natural continuous sound eg person talking
• digital data is captured by computer and stored in binary
• the higher the sampling rate, the more accurate the representation of the original waveform will be
• a sample rate is the number of times per second that an analogue signal is sampled to create digital data
• bit depth refers to how many bits are used to represent each sample
• sample rate = sample per regular intervals
• sample rate: the number of samples taken per second by the microphone or analogue to digital converter
• sample resolution: amount of bits per sample
• What is the main topic of episode 4 in the series?

  Sound quality improvement
• Why do we need to convert sound to digital form?

  Computers cannot store continuous analog sound
• What are the two key terms related to sound discussed in this episode?

  Sampling rate and sample resolution
• How is the sampling rate measured?

  In Hertz
• What is the sampling rate for CD-quality sound?

  44,100 Hertz
• What does a sound measurement at a given point in a sound file refer to?

  Sampling
• What does the amplitude in a sound wave represent?

  The ups and downs of the sound wave
• How does the accuracy of a recreated sound wave relate to sampling?

  More samples lead to more accurate recreation
• What happens if the sampling rate is too low?

  The recreated sound will differ from the original
• Why are telephone conversations sampled at a lower rate than CDs?

  Voice accuracy is less critical than music
• What is the trade-off when increasing the sampling rate?

  Larger file sizes require more bandwidth
• What is sample resolution similar to in images?

  Color depth
• How does increasing sample resolution affect sound accuracy?

  More bits lead to more accurate sound
• What is the formula to calculate the file size of a sound clip?

  Length × Sample Rate × Sample Resolution
• How do you convert bits to bytes?

  Divide by 8
• If a sound clip is 10 seconds long, sampled at 100 Hertz, and has a resolution of 4 bits, what is the file size in bytes?

  500 bytes
• How would you calculate the file size for an 8-second sound clip sampled at 50 Hertz with a resolution of 2 bits?

  Divide the result by 8
• What is the significance of knowing the sample rate and resolution in sound recording?

  They determine the quality and file size
• What is the result of doubling the number of samples taken?

  Better representation of the original wave
• What is the sampling rate for telephone conversations?

  8,000 Hertz
• Why is it important to sample sound at a high frequency?

  To match the original sound accurately
• How does sample resolution affect the number of values recorded?

  More bits allow more values to be recorded
• If a sound file is 40,000 bytes, how would you find the length of the sound clip if the sample rate is 20,000 and resolution is 8 bits?

  Divide 40,000 by 20,000
• What is the output of sound sampling rate?

  It affects sound quality
• What happens to the file size as the sample resolution increases?

  The file size increases
• How does the number of samples per second relate to sound quality?

  More samples improve sound quality
• What is the relationship between sample rate and bandwidth requirements?

  Higher sample rates require more bandwidth
• What is the significance of the term "Hertz" in sound sampling?

  It measures the frequency of samples
• How does the concept of sample resolution relate to sound accuracy?

  Higher resolution leads to more accurate sound
• What is the impact of insufficient sampling on sound reproduction?

  It leads to loss of sound detail
• If you have a sound clip of 5 seconds, sampled at 100 Hertz with a resolution of 4 bits, what is the total number of bits?

  4,000 bits
• What is the purpose of sampling in sound recording?

  To convert analog sound to digital