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. Measure of the amplitude of a longitudinal wave






2. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






3. 1st commercially successful AoE format for the transmission of digital audio - video - and control signals over 64- channel 100Mbps Ethernet networks






4. The frequency above or below which attenuation begins in a filter circuit






5. Voltage -> Dither -> Anti-Aliasing (Low Pass Filter) -> Sample & Hold Circuit -> Successive Approximation/Quantizer --) 100111010 (PCM Audio File)






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






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






8. 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.






9. Very selective method of lowering buffer levels by halting different levels of audio processing






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






11. 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






12. 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






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






14. In order to play multiple channels at one time data is buffered as read to disk; Latency happens between play command & beginning of playback






15. EDL; Final list of samples used in the audio editing process; Identified by time code






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






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






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






19. A network communications protocol that specifies how machines will exchange data; Uses a broadcast system in which one machine transmits its message on the communication medium and the other machines listen for messages directed to them






20. 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






21. 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.






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






23. Increases or decreases the digital signal so that the loudest sample is brought up to 0dBfs; Uses all bits from dynamic range and makes it even from track to track






24. The process of reducing the space required to store data by efficiently encoding the content.






25. 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






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






27. Mixing data and control characters in a single operation






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






29. Take up half as many bits (50%); Algorithm can keep same quality by lossing the stereo track






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






31. EBU






32. When recording you want the smallest buffer available; When mixing you want the largest buffer available






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






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






35. Increases D/A sample rate from nominal rate to oversampling rate by turning series multi- bit PCM samples into 1- bit samples; (ex. => 44.1kHz sample rate converted to 2.8MHz and simultaneously converts multi- bit samples to 1- bit); Low Pass Filter






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






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






38. Represents the amplitude component of the digital sampling process; Technique of incrementing a continuous analog event into a discrete set of binary digits (bits)






39. 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);






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






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






42. 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'






43. 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






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






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






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






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






48. The mathematics - algorithms - and the techniques used to manipulate signals after they have been converted to digital form






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. A method of representing real numbers using a mantissa and an exponent