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






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






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. 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)






5. Signal voltage is relayed to a register from sample- and - hold circuit; Holds reference frequencies in binary form that decrease in value; Finds approximated value & assigns binary number accordingly






6. 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'






7. Measures the highest levels of a signal being recorded or mixed; Monitors for clipping - which occurs at 0dBFS); Does not always reflect perceived volume of signal






8. 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






9. Full Scale; Type of metering that measures level in digital recording system; Recording and Mixing levels should NEVER exceed 0dB FS in digital audio or clipping will occur






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






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






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






13. Multi-Bit Words; (Pulse Code Modulation)






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






15. Method used in digital recording and reproduction in which a signal is sampled at various points and the resulting value is translated into binary numbers






16. A time regulator that makes all samples and bits to align when working with interconnected digital devices; Basically a signal that all of the digital devices refer to when operating.






17. Eight channel digital surround sound system by Dolby






18. ABR; Codecs that encode data by determining how dense or sparse areas of the audio are while also keeping bit rate within specified limits to avoid rebuffering






19. 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






20. Low Pressure; Part in a longitudinal wave where the particles are spread apart






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






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






23. Six channel (five speakers and one subwoofer for bass) digital surround sound system by Dolby






24. Describes acceptable data - performances both offered and essential for a disc player - and the complete user experience






25. AES






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






27. If a signal is sampled at a rate higher than twice the highest significant signal frequency and at evenly spaced intervals - then the samples contain all the information of the original signal






28. 16-Bit; 44.1 kHz; PCM; Stereo






29. Channels are processed one at a time and the results are stored on multiple CPU buffers that alternately send data as DAW requests the data for playback; First few seconds are relayed to the buffer prior to processing and playback and it continuously






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






31. Electromagnetic receptor that detects the radiation known as visible light






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






33. 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.






34. 15.9 GB; DS/DL






35. 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






36. 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)






37. 4.38 GB; SS/SL






38. Subtract place values from the decimal number and place ones or zeros in the correct places






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






40. The number of compressions or rarefactions in one second; The higher the frequency the more compressions & rarefactions per second; Measured in Hertz






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






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






43. 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






44. Roughly around 1 -130 ft/s






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






46. 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






47. 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






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






49. 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






50. Decibels Full Scale