sound processing

Question 1

sound features

Answer 1

volume, loudness, frequency, pitch

Question 2

frequency domain

Answer 2

representation of a signal based on how much information is contained at diefferent frequencies

Question 3

harmonics

Answer 3

component frequencies of a fundamental frequency

Question 4

Fourier series coefficient for k=0

Answer 4

DC component

Question 5

what is the maximum frequency that can be detected using FFT

Answer 5

the Nyquist frequency = Fs/2

Question 6

spectogram

Answer 6

visual representation of the spectrum of frequencies of a signal as they vary with time

Question 7

noise

Answer 7

all unwanted signals contaminating the useful signal

Question 8

filter

Answer 8

a system designed to maximise the useful signal, while removing the noise

Question 9

finite impulse response

Answer 9

type of digital filter in signal processing that has a finite duration response to an input signal

Question 10

infinite impulse response

Answer 10

have an impulse response that extends infinitely into the past and future

Question 11

random or white noise

Answer 11

manifested by small fluctuations in the measured signal values

Question 12

frequency response

Answer 12

describes how its output amplitude and phase change with respect to different input frequencies

Question 13

passband

Answer 13

refers to the frequencies that passed

Question 14

stopband

Answer 14

refers to the frequencies that are blocked

Question 15

transition band

Answer 15

refers to the frequencies that in between passed and blocked

Question 16

cutoff frequency

Answer 16

division between transition and band and passband

Question 17

filters in time domain

Answer 17

moving average filter

Question 18

moving average filter

Question 19

filters in frequency domain

Answer 19

low-pass
high-pass
band-pass
band-reject
Notch filter

Question 20

low-pass filter

Answer 20

suppresses the high frequencies

Question 21

high-pass filter

Answer 21

lets only high frequencies pass

Question 22

band-pass filter

Answer 22

lets only a range of frequencies pass

Question 23

band-reject filter

Answer 23

block a range of frequencies

Question 24

Notch filter or narrow band reject filter

Answer 24

attenuates several singular frequencies while preserving the rest

Question 25

frequency spectrum analysis

Answer 25

aims to identify which frequencies are present in a time-varying signal, at a given moment

Question 26

Fourier analysis

Answer 26

turn a time-varying signal into a frequency-varying signal

Question 27

Fourier series

Answer 27

mathematical representation that allows a periodic signal to be expressed as the sum of an infinite series of sinusoidal functions

Question 28

Fourier coeffiecent

Answer 28

tell us which frequency is present in the signal and to what extent

Question 29

What part of the FFT vector is useful?

Answer 29

only the first half, because the second half is a mirror of the first