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






2. The continuous loss of signal strengths as a signal travels through a medium






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






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






5. 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






6. CobraNet; EtherSound; Dante; AVB (currently under development)






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






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






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






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






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






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






13. 1.) Bit Rate x Sample Rate (you'll get b/sec) 2.) Multiply by 60 if converting seconds to minutes 3.) Divide by 8 to convert bits to Bytes and get B/min 4.) Divide by 1 -024 to get KB/min and keep doing it until you get desired bit rate specification






14. Waveform of a pure tone showing simple harmonic motion






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






16. 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






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






18. As sample rate is increased more room is created for a smoother slope of the attenuation band because Nyquist limit extends well beyond range of hearing with each increase






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






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






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






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






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






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






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






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






27. 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)






28. 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






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






30. 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






31. 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)






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






33. Measurement at regular intervals of the amplitude of a varying waveform (in order to convert it to digital form); There must be a minimum of 2 samples for each cycle in a waveform






34. Uses entropy coding as the basis; Computer data compression algorithm that packages files such as .ZIP & .RAR






35. The ability of a digital system to perform complex DSP without running into problems with overflow or loss of resolution






36. The difference between the analog value and the approximated digital value due to the 'rounding' that occurs while converting the analog signal to digital






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






38. 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






39. 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.






40. 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






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






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






43. The more bits allocated during quantization - the more accurate the measurement






44. 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.






45. Pertaining to hearing or sound; Combination of the intensity of air pressure molecules with amplitude






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






47. 8.75 GB; DS/SL






48. 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






49. High channel count; 64 channels on one cable; Coaxial cable with BNC connector or fiber optic with ST1 connector






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