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






2. 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






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






4. 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






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






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






7. 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






8. 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






9. Mixing data and control characters in a single operation






10. 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






11. Sample Rate x Bit Depth x # of Channels






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






13. 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






14. Very selective method of lowering buffer levels by halting different levels of audio processing






15. Used as the main disc from which other discs are made; Composed of ground glass with a very fine photoresistor layer; An imaging laser burns pit and land patterns in preparation for duplication






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






17. Specific set of instructions for carrying out a data reduction technique that determines how to 'save' binary data information efficiently






18. Same as 'aliasing'






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






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






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






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






23. 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






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






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






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






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






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






29. 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);






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






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






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






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






34. The frequency above or below which attenuation begins in a filter circuit






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






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






37. The amount of energy at each wavelength






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






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






40. Waveform of a pure tone showing simple harmonic motion






41. 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






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






43. How Loud (Y-Axis) & How Fast (X-Axis)






44. 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






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






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






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






48. 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






49. 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






50. 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