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. Process that begins with a fast FFT analysis of the spectra of two input signals - then the multiplication of like frequencies - and IFFT to finalize the process






2. 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






3. Stores only one copy of a stereo signal and assigns it to both channels in order to save 50% of original bandwidth






4. Lossless Format; Can hold up to 25GB on a single- layer disc and 50GB on a dual- layer disc






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






6. 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






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






8. 4.38 GB; SS/SL






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






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






11. 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






12. Six channel (five speakers and one subwoofer for bass) digital surround sound system by Dolby






13. Inner ear component that attaches to the stapes and helps to decrease the amplitude of vibrations; Causes the masking phenomenon






14. 'Capturing' part of digital audio; Never captures a signal perfectly






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






16. 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






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






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






19. Decibels Full Scale






20. 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






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






22. Allows for an internal sample rate at multiples of the input and output rates; Alleviates the need for steep 'brickwall' filters; Often combined with internal '1- bit' processing; Increases smoothing effect






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






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






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






26. 16-Bit; 44.1 kHz; PCM; Stereo






27. Digital (binary) measurements of how long each pulse is either on or off; Width of increasing voltage or decreasing voltage is assigned a 1 or 0 respectively






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






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






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






31. 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






32. 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






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






34. Mixing data and control characters in a single operation






35. 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)






36. 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






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






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






39. ABR; Codecs that encode data by determining how dense or sparse areas of the audio are while also keeping bit rate within specified limits to avoid rebuffering






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






41. Eight channel digital surround sound system by Dolby






42. 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






43. 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






44. EBU






45. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






46. Playback; I/O Connections; CPU (Streaming); Conversion from DAW or Software






47. 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






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






49. 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)






50. AES