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. Father of modern information theory; Solidified the Nyquist Theory by adding the concept that bits per second (binary representation of audio signals) must be at equal intervals to accurately represent data






2. HD Audio format; Lossless Compression; 24- bit/96 kHz; 5.1 Surround or 24- bit / 192 kHz stereo sound






3. 4.38 GB; SS/SL






4. Lossless Format; Can hold up to 25GB on a single- layer disc and 50GB on a dual- layer disc






5. Based on psychoacoustics - these are the basis of frequency analysis for a perceptual codec;






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






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






8. The amount of energy at each wavelength






9. Decibels Full Scale






10. 12.33 GB; DS/ML






11. Series of dots and dashes representing the letters of the alphabet; Most common letters are represented by the shortest dots and dashes; Example of entropy coding






12. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






13. Anytime bit depth is reduced the gap gets bigger so more dithering is required






14. Perceptual coding technique that uses louder sounds of a similar frequency to decide what information is to be saved during data reduction






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






16. Apple Lossless; Windows Media Lossless; DTS HD Master Audio; Dolby True HD; FLAC






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






18. Psychoacoustic model of data reduction used for general audio compression that aims to transmit only features perceptible to the human ear; Useful for mastering streaming media






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






20. (AES/EBU); 110O - 2- channel balanced digital audio cable with an XLR connection; NOT a mic cable!!






21. The frequency range that is allowed through a filter






22. Occurs as data is assembled into meaningful bits or information and as left & right channels are separated






23. Waveform of a pure tone showing simple harmonic motion






24. Only 2 digits used; The value of each place (ones - hundreds - etc.) are as follows from greatest to least: 128 - 64 - 32 - 16 - 8 - 4 - 2 - 1






25. 'Reconstructing' part of digital audio






26. High Pressure - Part of a longitudinal wave where the particles of the medium are close together






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






28. The elapsed time it takes for a packet of data to arrive at its destination; Lagging or pause of an audio signal as digital processing occurs; Can be managed utilizing several forms of 'audio monitoring'






29. 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.






30. Describes various optical disc characteristics including the size and shape of the disc - the size of pits - the speed at which the disc spins - and a multitude of aspects regarding the specifications of the player itself






31. The loudest point of a Full Scale system






32. 16-Bit; 44.1 kHz; PCM; Stereo






33. EBU






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






35. Process of building a complex tone by starting with the fundamental frequency and adding pure tone harmonics






36. Reduces A/D sample rate from the oversampled rate to nominal rate by turning series of one- bit samples into a series of multi- bit PCM samples; (ex. => 2.8MHz sample rate converted to 44.1kHz and simultaneously converts 1-Bit samples to multi- bit);






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






38. (Time Based) Frequency: Aliasing; Anti-Aliasing Filter; Sample Rate; Nyquist Limit






39. Level above which audible sounds are painful (125 - 130 db)






40. Splits the input signal and mixes it with an analog copy so that no latency is present






41. Overtones that contribute to the timbre of a sound and make up a complex waveform's physical characteristics






42. 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






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






44. Same as 'aliasing'






45. Defines the number of sample per second taken from a continuous signal to make a discrete signal; Governs the frequency response of digital audio






46. Very quiet digital amplifier that produces a series of output pulses with the audio signal coded the same as the width of the output pulses; Pulses are used to represent wave forms and are either on or off; Intense signals have long pulses with short






47. A situation where a calculated value cannot fit into the number of digits reserved for it






48. 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






49. 'Capturing' part of digital audio; Never captures a signal perfectly






50. Roughly around 1 -130 ft/s