Sound Design Sound 5

Question 1

In digital audio, the Nyquist theorem states that to accurately capture a frequency f, the sample rate must be:

Accepted Answer

At least 2 times f

Answer

The Nyquist theorem requires a sample rate of at least twice the highest frequency to be reproduced in order to avoid aliasing artifacts.

Question 2

Aliasing in digital audio is caused by:

Accepted Answer

Sampling frequencies above the Nyquist limit, which fold back into the audible range

Answer

When a signal contains frequencies above half the sample rate (Nyquist frequency), those frequencies fold back and appear as false lower-frequency artifacts called aliases.

Question 3

What is the purpose of dithering in digital audio?

Accepted Answer

To add low-level noise that randomizes quantization errors and reduces audible distortion

Answer

Dithering adds a small amount of noise to a signal before reducing bit depth, which randomizes quantization errors and prevents them from becoming correlated, audible distortion.

Question 4

In digital audio, bit depth primarily determines:

Accepted Answer

The dynamic range and resolution of amplitude values

Answer

Each additional bit of bit depth adds approximately 6 dB of dynamic range; 16-bit audio yields ~96 dB and 24-bit yields ~144 dB of theoretical dynamic range.

Question 5

Which file format stores audio data without any compression, preserving the exact original samples?

Accepted Answer

WAV (PCM)

Answer

WAV files using PCM (Pulse Code Modulation) encoding store raw uncompressed audio samples, making them lossless and bit-for-bit accurate.

Sound Design Practice Test

Sound Design Practice Test

Sound Design Sound 5