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. Decibels Full Scale






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






3. Used when the reference pressure of a sound is 20 microPa (0.00002); Sound Pressure Level; Measure of amplitude






4. Reduces the percieved distortion due to quantization error; Low level white noise source is introduced to make the profile of the quantization 'noise' more irregular; Useful when reducing the number of bits per word in a signal (i.e. when converting






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






6. The amount of energy at each wavelength






7. Samples are duplicated and the playback sampling rate correspondingly increased; Significantly raises the Nyquist limit to a range well beyond human hearing; Processing 'pushes' the distortion resulting from quantization error into these higher frequ






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






9. A frequency specified for a filter (digital or electronic) the marks the point at which the frequency content of a signal is altered +/- 3dB






10. Eight channel digital surround sound system by Dolby






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






12. 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






13. 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






14. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






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






16. 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






17. 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






18. Have odd numbered harmonics






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






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






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






22. Measure of the amplitude of a longitudinal wave






23. Algorithm uses matrix of a mid/side microphone pair to determine a side signal & that signal is reduced then distributed as code in stereo






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






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






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






27. 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






28. 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






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






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






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






32. When recording you want the smallest buffer available; When mixing you want the largest buffer available






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






34. 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






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






36. The set of rules that computers use to move files from one computer to another on an internet






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






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






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






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






41. 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






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






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






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






45. 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






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






47. Roughly around 1 -130 ft/s






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






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






50. Defines the number of sample per second taken from a continuous signal to make a discrete signal; Governs the frequency response of digital audio