COMD 5070 Exam 3 2025/2026 Exam
Questions and Answers | 100% Solved
4 features of the scientific method: - 🧠 ANSWER ✔✔empirical,
deterministic, predictive, parsimonious
Octave - 🧠 ANSWER ✔✔a doubling or halving of a frequency
How many semitones in an octave? - 🧠 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 - 🧠 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 - 🧠 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 - 🧠 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 - 🧠 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 - 🧠 ANSWER ✔✔allows high frequencies and attenuates
low frequencies
Low pass filter - 🧠 ANSWER ✔✔allows low frequencies and attenuates high
frequencies
, Band Pass filter - 🧠 ANSWER ✔✔Removes high and low frequencies but
lets through the frequencies in the middle
Band reject filter - 🧠 ANSWER ✔✔Allows all frequencies except for a
specific band in the middle.
Fourier transform - 🧠 ANSWER ✔✔a way to analyze complex sounds by
separating them into their components
How to do a Fourier transform - 🧠 ANSWER ✔✔You take a time domain
wave form ( microphone signal - time on x and amplitude on Y) you apply
the fourier transform to it and it gives you a frequency domain wave form (
line spectrum) which represents a slice in time that has frequency on x and
amplitude on y. It's like parsing light through a spectrum which shows all of
the colors. So you can now hear all of the individual sounds that make up
the harmonic series - this is the spectrum / frequency/domain display.
Similar to a list of ingredients of a cake.
time-domain display - 🧠 ANSWER ✔✔has time on the X axis and Amplitude
on the Y axis and shows a waveform that represents sound directly. It
shows air pressure changes over time
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED 3
Questions and Answers | 100% Solved
4 features of the scientific method: - 🧠 ANSWER ✔✔empirical,
deterministic, predictive, parsimonious
Octave - 🧠 ANSWER ✔✔a doubling or halving of a frequency
How many semitones in an octave? - 🧠 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 - 🧠 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 - 🧠 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 - 🧠 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 - 🧠 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 - 🧠 ANSWER ✔✔allows high frequencies and attenuates
low frequencies
Low pass filter - 🧠 ANSWER ✔✔allows low frequencies and attenuates high
frequencies
, Band Pass filter - 🧠 ANSWER ✔✔Removes high and low frequencies but
lets through the frequencies in the middle
Band reject filter - 🧠 ANSWER ✔✔Allows all frequencies except for a
specific band in the middle.
Fourier transform - 🧠 ANSWER ✔✔a way to analyze complex sounds by
separating them into their components
How to do a Fourier transform - 🧠 ANSWER ✔✔You take a time domain
wave form ( microphone signal - time on x and amplitude on Y) you apply
the fourier transform to it and it gives you a frequency domain wave form (
line spectrum) which represents a slice in time that has frequency on x and
amplitude on y. It's like parsing light through a spectrum which shows all of
the colors. So you can now hear all of the individual sounds that make up
the harmonic series - this is the spectrum / frequency/domain display.
Similar to a list of ingredients of a cake.
time-domain display - 🧠 ANSWER ✔✔has time on the X axis and Amplitude
on the Y axis and shows a waveform that represents sound directly. It
shows air pressure changes over time
COPYRIGHT©NINJANERD 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED 3
