3. Audio Recording & Reproduction Flashcards
(32 cards)
What is the main purpose of recording and reproducing audio?
C. Storage
Storage is essential for retaining audio data for playback and manipulation.
What is the typical sampling rate used in digital audio recording?
D. 44,100 samples/s
This rate is standard for CD audio quality.
According to the Nyquist theorem, a 44.1 kHz sampling rate can capture frequencies up to:
A. 22,050 Hz
The Nyquist theorem states that the maximum frequency that can be accurately captured is half the sampling rate.
A sine wave can be represented mathematically as:
C. y = sin(x)
Sine waves are fundamental in sound wave analysis.
What is the term for a waveform composed of multiple sine waves?
C. Complex waveform
Complex waveforms are common in real-world audio signals.
Which waveform contains only odd harmonics with amplitude 1/N?
C. Square
Square waves are a fundamental concept in waveform analysis.
In a triangle wave, the amplitude of harmonics follows the pattern:
B. 1/N², every other × (−1)
This pattern reflects the decreasing amplitude of harmonics in triangle waves.
According to Fourier’s theorem, any waveform with a fundamental frequency F can be decomposed into:
C. Multiples of F (harmonics)
Fourier’s theorem is key in understanding signal processing.
Name the two types of aperiodic waveforms?
Continuous (noise) and transient (pulse)
Aperiodic waveforms are important in noise analysis.
What is the function of an audio filter?
C. It selectively attenuates or amplifies certain frequencies
Filters are crucial for shaping audio signals.
A filter that allows only high frequencies to pass is called a:
B. High-pass filter
High-pass filters are widely used in audio processing.
Which type of filter passes frequencies between two set points and blocks others?
D. Band-pass
Band-pass filters are essential in various audio applications.
The basilar membrane acts similarly to a:
B. Filter bank
The basilar membrane helps in frequency analysis in the ear.
What is the RMS (Root Mean Square) used for in spectral analysis?
C. Measuring average amplitude
RMS is a standard measure in audio signal analysis.
In an amplitude spectrum, the vertical axis typically represents:
B. Amplitude in decibels
This representation is standard in audio engineering.
What is added to the spectrum to create a spectrogram?
C. Time dimension
Spectrograms visualize how sound changes over time.
What does the Fourier theorem allow us to do?
C. Decompose waveforms into sine waves
This is fundamental for analyzing complex signals.
The spectrum of a sound shows:
C. Frequencies and amplitudes of sine wave components
Understanding the spectrum is key in audio analysis.
How is the spectrum of a complex signal calculated?
C. Using a bank of band-pass filters
This method is commonly used in signal processing.
What happens when a recording is made with too low amplitude?
C. It results in poor waveform and spectrogram quality
Low amplitude recordings can lead to significant loss of detail.
Pitch is our perception of:
Repetition frequency ## This links physical frequency with perceptual pitch in auditory science.
A repetition period of 10 ms corresponds to what frequency?
100 Hz ## Frequency is the inverse of the period: 1 / 0.01 s = 100 Hz.
Speeding up a recording makes the pitch sound:
Higher ## Shorter repetition periods mean higher frequency, thus higher pitch.
Which category includes square, triangle, and sawtooth waves?
Complex periodic waveforms ## These are formed by combining multiple harmonics in specific patterns.
