Analogue and Digital Recording Flashcards
What are the only values a digital signal can possess?
0 or 1
What does the process of analogue to digital conversion involve?
Taking digital samples of the momentary amplitude of a waveform
In analogue to digital conversion, what is a continuous analogue signal converted into?
A series of binary numbers
With regards to analogue to digital conversion, what is the sample rate?
The number of times the amplitude of the analogue signal is read
In analogue to digital conversion, what is 1Hz equal to?
1 sample of the waveform’s amplitude taken every second
What sample rate is CD quality?
44.1kHz
What sample rate is DVD quality?
48kHz
Why is there an argument against recordings at a sample rate higher than 48kHz sounding better?
Because the limitations of human hearing mean you would very unlikely hear any difference
What effect does the sample rate have on the frequency response of equipment?
The higher the sample rate, the greater the highest frequency captured
What is Nyquist’s theorem?
The sample rate of a digital system should be a minimum of twice the highest frequency captured
What occurs when the sample rate is not high enough?
Aliasing
What happens to frequencies above the Nyquist frequency?
They are captured and incorrectly recreated within the audible range below the Nyquist frequency
What does the incorrect recreation of frequencies above the Nyquist frequency manifest as?
Artefacts
In analogue-digital conversion, what is the bit depth?
The level of detail the amplitude is measured to for each sample
What effect does a higher but depth have on the signal?
The greater the bit depth, the greater the dynamic range, and therefore the signal-to-noise ratio
