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






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






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






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






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






6. A sample- by- sample operation on two signals






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






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






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






10. Governs the frequency response of a digital system; The highest- frequency component that can be captured with a sampling rate; always 1/2 of sampling rate; Also called the limiting frequency






11. Roughly around 1 -130 ft/s






12. Measuring equipment in A/D conversion that processes voltage and provides a value for that voltage






13. 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






14. Allowance of noise floor below that which is required for the final product






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






16. 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)






17. 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






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






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






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






21. Discrete incremental distinctions made between the value of one sample and the next; Breaks down bit depth into a series of evenly spaced intervals






22. 8- in/8- out on one cable; 25- pin D- sub connector






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






24. MPEG; Standardizing body of audio coding






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






26. ADAT Optcal; 8- in/8- out on two cables; Fiber- optic - TOSLINK connector






27. 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






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






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






30. Data reduction technique that selectively removes original information in order to significantly reduce the file size; Some data is lost; Files can be reduced up to 99% in size (90% with no perceived sound quality loss); Bit rate effects the perceive






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






32. 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






33. 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






34. Number of bits per second processed when sampling sound; (Sampling Rate x Bit Depth) = Resolution






35. 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






36. 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)






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






38. The amount of energy at each wavelength






39. Difference in brightness between land and pit on a CD Physical Format






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






41. 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






42. Each bit in the bit depth is equal to a _____ increase in dynamic range






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






44. 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






45. 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






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






47. 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






48. 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






49. 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);






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