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. 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






2. Most significant lossless coding technique in current use; Measure of disorder in which long strings of data are represented by short symbols and uses the shortest symbols to represent the most common repetitive audio data maximizing data reduction






3. Eight channel digital surround sound system by Dolby






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






5. 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






6. Measure of the amplitude of a longitudinal wave






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






8. 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






9. 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






10. Joint-Stereo Technique; Since the human brain is unable to localize sounds at high frequencies well sounds above 9 kHz threshold are encoded in mono






11. Contains all even and odd harmonics associated with a fundamental tone - making it a rich source for modeling other sounds; Amplitude of each overtone decreases exponentially as a ratio of the harmonic's frequency to that of the fundamental






12. A drive that can read and write on optical media that hold up to 50 GB on two layers; 24- bit/96 kHz for 8-Channel; 24- bit/192 kHz for 6-Channel






13. 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






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






15. 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






16. 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






17. Sum of all harmonics; Sum of sine and cosine waves which have frequencies f - 2f - 3f - 4f...






18. EBU






19. MPEG; Standardizing body of audio coding






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






21. Computer program or device capable of encoding and/or decoding a digital data stream with the end result being a reduced file size






22. 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






23. Found that aliasing was always a problem no matter how fast you sample; Less data recorded but more accurate; 2 samples per wave length.






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






25. 7.95 GB; SS/DL






26. Sony and Philips optical disc format; Utilizes sigma delta DSD to offer higher resolution; 1- bit; 2.8224 MHz; 6-Channel






27. Accuracy with which an electronic system reproduces the sound or image of its input signal






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






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






30. 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);






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






32. 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






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






34. Measure of sound pressure over the frequency spectrum - for which a listener perceives a constant loudness when presented with pure steady tones






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






36. 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






37. 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






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






39. 8- in/8- out on one cable; 25- pin D- sub connector






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






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






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






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






44. 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






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






46. 8.75 GB; DS/SL






47. 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






48. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






49. 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






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