COMD 5070 exam 3 fully solved

COMD 5070 exam 34 features of the scientific method: - correct answer empirical, deterministic, predictive, parsimonious Octave - correct answer a doubling or halving of a frequency How many semitones in an octave? - correct answer 12. each semitone is a non-linear step in terms of # of Hz from one semitone to the next. However, they all sound equal to us. Sampling rate - correct answer The number of snapshots of the sound in time. ( in Hz) 10 samples is a 10 Hz recording. Generally, the higher the sampling rate, the higher the fidelity of the recording. Graphic representation of the join the dots graph, the more dots, the better the image, the fewer, the cruder. A higher sampling rate will take up more space and require higher processing power. Nyquist frequency - correct answer half the sample rate. You determine the highest frequency you want to include in your recording and double it, this will ensure that the playback will go at least as high as the original signal. Nyquist determines the highest frequency you can reproduce in playback. CD sampling rate is 44,100 and it stores signals up to 22,050 Hz. Aliasing - correct answer When sampling too slowly, you will inaccurately record the original signal. High, original frequencies will be improperly recorded as lower frequencies. Think of the sine wave, where only certain dots were captured, so the original waveform is "smoothed out" or aliased. How to prevent aliasing - correct answer This can be prevented with a low pass filter at the nyquist frequency, to keep out the high frequencies that might be misrepresented. High pass filter - correct answer allows high frequencies and attenuates low frequencies Low pass filter - correct answer allows low frequencies and attenuates high frequencies