What can every natural signal be converted into and what does it indicate?
Sequence of numbers that indicates the magnitude of the signal
What is the numerical representation of an acoustical signal called?
Digital signal
What is the digital signal made up of?
Digital code
How can the digital code be used?
Store, process, and transmit information
What is an analog signal and what does it represent?
A continuous signal that represents all point in time
What is a digital signal and what does it represent?
Snapshots of time
What advantage do digital signals have over analog signals?
Digital signals are more immune to noise and distortion
What types of operations are done on a digital signal?
Mathematical (multiplication, division, addition, subtraction)
What do these operations allow us to do in terms of modifying the signal?
Amplify the signal, filter out noise, finely tune the signal
In what types of modern technology do we find digital signal processing (DSP)?
Computers, digital hearing aids, CD players
What do digital signals represent?
Natural signal in a sequence of numbers
What do digital signals need to be converted into prior to digital signal processing?
Binary code
What are the two states of a given variable?
0 and 1
What is the smallest amount of information that can be processed by a binary computer?
Bit
Explain the conversion of an acoustic signal:
The signal is converted from analog to digital using analog to digital converter, the signal is processed by the digital circuitry, then translated back into an analog signal using a digital to analog converter
What are the two basic steps to convert analog signals into digital code?
A/D and D/A
What is sampling?
Snapshots taken per second of time
What is the term used for the number of snapshots taken per second of time?
Sampling rate
How do the number of snapshots taken influence the representation of the original wave?
The more snapshots taken, the more natural the signal sounds to the original wave
What needs to be done to ensure no loss of information during sampling?
The sampling rate should be at least twice the highest frequency in a sampled signal
What is the rule of sampling?
Nyquist-Shannon theorem
What is digitization?
The process of converting the quantitated values into binary form
Once the analog signal is converted into digital form, a variety of different processing techniques may be performed on the digital signal:
Filtering, amplifying, equalizing, compressing and limiting
What is the field of digital signal processing that concerns audio signals called?
Digital audio applications
