Test your basic knowledge |

Digital Audio

Subject : engineering
Instructions:
  • Answer 50 questions in 15 minutes.
  • If you are not ready to take this test, you can study here.
  • Match each statement with the correct term.
  • Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. Apple Lossless; Windows Media Lossless; DTS HD Master Audio; Dolby True HD; FLAC






2. Reduces the percieved distortion due to quantization error; Low level white noise source is introduced to make the profile of the quantization 'noise' more irregular; Useful when reducing the number of bits per word in a signal (i.e. when converting






3. Data is transmitted over fiber optic lines; Uses a TOSLINK connecter instead of an RCA type; Can transmit multi- channel audio; Not susceptible to ground hum and loops; Able to support far higher rates of data transfer over greater distances than coa






4. Cable used to transmit data; Inner cable is surrounded by a plastic insulator - which is surrounded by a wire mesh conductor that insulates the internal signal wire from external interference and an outer casing that functions as a ground






5. 1.) Taking a series of evenly- spaced measurements 2.) Signal contains no frequency components higher than half the sample rate






6. VBR; Most common & best data reduction technique; Codecs that encode data by determining how dense or sparse areas of the audio are; Can result in buffering issues






7. 8- in/8- out on one cable; 25- pin D- sub connector






8. Samples are duplicated and the playback sampling rate correspondingly increased; Significantly raises the Nyquist limit to a range well beyond human hearing; Processing 'pushes' the distortion resulting from quantization error into these higher frequ






9. Serial Copy Management System; main difference between AES3 & S/PIDF






10. Improper (false) sampling of high frequencies that cause much lower frequencies to be produced when the audio is reconstructed; Foldover happens at higher frequencies as harmonics reach levels that exceed the Nyquist limit.






11. More accuracy in low amplitudes and less in higher amplitudes






12. Removes high frequency images and noise and smoothes the stair case output coming from of the sample and hold circuit; Also called a SMOOTHING FILTER






13. Leaving space at beginning and ending of song for data crunching during mastering; Last step in mastering process






14. Playback; I/O Connections; CPU (Streaming); Conversion from DAW or Software






15. Single- pin RCA cable or fiber- optic TOSLINK connector used for digital transfer; 75O coaxial - 2- channel unbalanced; 'Consumer' format of AES3






16. Built into DAWs; Bits are added when signals are mixed together to avoid clipping






17. Number or variable that represents the number of times the base of a power is used as a factor; Defines magnitude






18. The difference in volume between the loudest and quietest sounds of a source






19. Measuring equipment in A/D conversion that processes voltage and provides a value for that voltage






20. Sony sigma- delta modulation based technology that bypasses the decimation and interpolation steps found in PCM converters






21. How Loud (Y-Axis) & How Fast (X-Axis)






22. Data reduction technique that selectively removes original information in order to significantly reduce the file size; Some data is lost; Files can be reduced up to 99% in size (90% with no perceived sound quality loss); Bit rate effects the perceive






23. Each bit in the bit depth is equal to a _____ increase in dynamic range






24. Number of bits used to represent the smallest unit of information in an audio file; Greater bit depth = better quality audio






25. More aggressive lossy data reduction techniques that require further manipulation of the stereo field; Examples are 'Intensity' & 'M-S'






26. DAW's and software must buffer when converting or bouncing and this latency can add up if not monitored






27. Digital and analog processing capability is combined on a single microchip allowing for 1- bit resolution at high sample rates






28. ADAT Optcal; 8- in/8- out on two cables; Fiber- optic - TOSLINK connector






29. Signal conversions are mixed with playback tracks resulting in near-zero latency






30. Root Mean Square; Refers to taking the square root of all instantaneous amplitudes; Takes the average of those squares; (-6 Peak Level is approximately equal to -20 RMS)






31. Signal that uses variable voltage to create continuous waves resulting in an inexact transmission






32. Algorithm uses matrix of a mid/side microphone pair to determine a side signal & that signal is reduced then distributed as code in stereo






33. ADPCM; Pulse code modulation that produces a digital signal with a lower bit rate than standard PCM; Records only the difference between samples






34. Used as the main disc from which other discs are made; Composed of ground glass with a very fine photoresistor layer; An imaging laser burns pit and land patterns in preparation for duplication






35. 15.9 GB; DS/DL






36. Branch of psychology concerned with the subjective perception of sound






37. Rate at which energy is drawn from a source that produces a flow of electricity in a circuit; Expressed in volts






38. Digital Word -> Series of Resistors (each with assigned charges) -> Sample- and-Hold Circuit -> Anti-Imaging Filter (Smoothing Filter) -> Reconstructed Sample






39. The art of deciding where to place a processor in signal flow based on how that processor will be influenced by the other processors in the path






40. Amplitude meter that takes the square root of all instantaneous amplitudes and averages them to find a mean and squares that value; Useful with particularly complex waveforms






41. Twice as many samples as the highest frequency at minimum; Sampling rate totally controls frequency response






42. Eliminates frequencies above the Nyquist limit from becoming samples; Occurs prior to quantization






43. Sony and Philips optical disc format; Utilizes sigma delta DSD to offer higher resolution; 1- bit; 2.8224 MHz; 6-Channel






44. Stores only one copy of a stereo signal and assigns it to both channels in order to save 50% of original bandwidth






45. (Amplitude Based) Amplitude: Voltage; Quantization; Bit Depth; Quantization Intervals; Quantization Noise; [Signal:Quantization Noise Ratio]; Dither; Dynamic Range






46. Softest sound that can be heard by the average human ear (0 dB)






47. Allows for an internal sample rate at multiples of the input and output rates; Alleviates the need for steep 'brickwall' filters; Often combined with internal '1- bit' processing; Increases smoothing effect






48. Contains all even and odd harmonics associated with a fundamental tone - making it a rich source for modeling other sounds; Amplitude of each overtone decreases exponentially as a ratio of the harmonic's frequency to that of the fundamental






49. A digital filter's time domain output sequence when the input is a single sample is input






50. Ratio of magnitude of the analytical signal to the magnitude of the background noise signal