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. Toshiba developed digital audio interface utilizes fiber optics as a transmission medium.






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






3. Reference voltage determined by summing the voltage values of a predetermined number of previous samples; Numbers of 1 in row = waveform peak; Numbers of 0 in row = waveform trough; Basis of Sony's Direct Stream Digital (DSD)






4. 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






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






6. 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






7. Digital (binary) measurements of how long each pulse is either on or off; Width of increasing voltage or decreasing voltage is assigned a 1 or 0 respectively






8. Having a repeated succession of waves or curves as in a sound waveform






9. Specific set of instructions for carrying out a data reduction technique that determines how to 'save' binary data information efficiently






10. Used when the reference pressure of a sound is 20 microPa (0.00002); Sound Pressure Level; Measure of amplitude






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






12. Also known as equal loudness curves; Graph that indicates the average ear sensitivity to different frequencies at different SPL levels (as volume increases - these curves flatten out)






13. French mathematician that noted that any complex sound can be broken down into a series of component pure tones






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






15. Snippets of time in which frequency analysis takes place in a perceptual codec






16. Measure of sound pressure over the frequency spectrum - for which a listener perceives a constant loudness when presented with pure steady tones






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






18. Decibels Full Scale






19. 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






20. 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






21. 8.75 GB; DS/SL






22. Mixing data and control characters in a single operation






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






24. A drive that can read and write on optical media that hold up to 50 GB on two layers; 24- bit/96 kHz for 8-Channel; 24- bit/192 kHz for 6-Channel






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






26. Circuit that seizes voltage values with each tick of an A/D device's internal clock






27. Method of representing an acoustic quantity with a series of binary numbers; Can have only specific individually distinct values






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






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






30. Based on Full Scale (dB/FS); -6dB represents a loss of one bit so account for this when calculating






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






32. AAC (Advanced Audio Coding); MP3; RA; WMA; OGG Vorbis; Dolby Digital/AC-3; DTS; ADPCM






33. Ultra low- latency - 512- channel (on a gigabit network) - less flexible AoE format; Routed like audio cables...not network cables






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






35. 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






36. Found that aliasing was always a problem no matter how fast you sample; Less data recorded but more accurate; 2 samples per wave length.






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






38. 1st commercially successful AoE format for the transmission of digital audio - video - and control signals over 64- channel 100Mbps Ethernet networks






39. 16-Bit; 44.1 kHz; PCM; Stereo






40. Circuit that interprets the meaning of the symbols as they were chosen and arranged by the encode






41. Industry Standards: -6 dB Peak = -20 RMS Meter






42. The set of rules that computers use to move files from one computer to another on an internet






43. 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






44. Data reduction technique that does not effect quality of original audio; No effect on original quality; Typically around 50% reduction; Exact reconstruction of digital code for the audio signal






45. Unit of measurement that is equal to one millionth of a meter






46. Unit of measurement that is equal to one billionth of a meter






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






48. RAM holds in memory audio data before it is transferred to the memory controller; Certain amount of data is processed before large amounts of data are streamed to prevent latency






49. The loudest point of a Full Scale system






50. Visual graph that shows how loud a sound is at different frequencies