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. Series of dots and dashes representing the letters of the alphabet; Most common letters are represented by the shortest dots and dashes; Example of entropy coding






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






3. 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






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






5. Ratio of magnitude of the analytical signal to the magnitude of the background noise signal






6. 8.75 GB; DS/SL






7. 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






8. Deviation from a normal - steady pulse or tick of a clock that contributes to misrepresentation of a signal; Result of small timing irregularities that become magnified during the transmission of digital signals as the signals are passed from one dev






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






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






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






12. 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






13. Twice as many samples as the highest frequency at minimum; Sampling rate totally controls frequency response






14. 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






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






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






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






19. 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






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






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. MPEG; Standardizing body of audio coding






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






24. Measure of the amplitude of a longitudinal wave






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






26. 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






27. 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






28. 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






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






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






31. 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






32. 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






33. The art of deciding where to place a processor in signal flow based on how that processor will be influenced by the other processors in the path






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






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






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






37. More aggressive lossy data reduction techniques that require further manipulation of the stereo field; Examples are 'Intensity' & 'M-S'






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






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






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






41. CBR; Codecs encodes data at a constant rate regardless of density of the audio file






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






43. 'Reconstructing' part of digital audio






44. HD Audio format; Lossless Compression; 24- bit/96 kHz; 5.1 Surround or 24- bit / 192 kHz stereo sound






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






46. 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






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






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






50. 4.38 GB; SS/SL