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. 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);






2. 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






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






4. 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






5. Mixing data and control characters in a single operation






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






7. 16-Bit; 44.1 kHz; PCM; Stereo






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






9. Data transmission protocol over which computer network traffic travels; Poorly suited to real- time transmission but numerous attempts have been made to harness the technology because of its flexible routing; Uses simple Cat5 cabling; Resists interfe






10. Number or variable that represents the number of times the base of a power is used as a factor; Defines magnitude






11. 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






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






13. 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.






14. 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






15. 15.9 GB; DS/DL






16. Method of sampling data at a higher resolution (higher sample rate) as a means of reducing harmonic content during D/A conversion; (x2) oversampling gets rid of all odd harmonic content






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






18. 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






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






20. 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)






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






22. 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.






23. Method of representing an acoustic quantity with a series of binary numbers; Can have only specific individually distinct values






24. A digital filter's time domain output sequence when the input is a single sample is input






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






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






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






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






29. 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






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






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






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






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






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






35. 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






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






37. 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






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






39. 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






40. 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






41. Overtones that contribute to the timbre of a sound and make up a complex waveform's physical characteristics






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






43. Circuit that interprets the meaning of the symbols as they were chosen and arranged by the encode






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






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






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






47. High Pressure - Part of a longitudinal wave where the particles of the medium are close together






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






49. Smallest interval measurable by a scientific instrument; Defined by bit rate (sample rate x bit depth)






50. 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