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. 1st commercially successful AoE format for the transmission of digital audio - video - and control signals over 64- channel 100Mbps Ethernet networks






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






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






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






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






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






7. Reference voltage determined by summing the voltage values of a predetermined number of previous samples; Numbers of 1 in row = waveform peak; Numbers of 0 in row = waveform trough; Basis of Sony's Direct Stream Digital (DSD)






8. (Time Based) Frequency: Aliasing; Anti-Aliasing Filter; Sample Rate; Nyquist Limit






9. The frequency range that is allowed through a filter






10. Electromagnetic receptor that detects the radiation known as visible light






11. The process of reducing the space required to store data by efficiently encoding the content.






12. 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






13. 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






14. 7.95 GB; SS/DL






15. 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






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






17. 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)






18. If a signal is sampled at a rate higher than twice the highest significant signal frequency and at evenly spaced intervals - then the samples contain all the information of the original signal






19. 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);






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






21. Signal conversions are mixed with playback tracks resulting in near-zero latency






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






23. The number of compressions or rarefactions in one second; The higher the frequency the more compressions & rarefactions per second; Measured in Hertz






24. 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






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






26. 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






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






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






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






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






31. 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






32. Uses entropy coding as the basis; Computer data compression algorithm that packages files such as .ZIP & .RAR






33. 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)






34. 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






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






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






37. AES






38. Softest sound that can be heard by the average human ear (0 dB)






39. Fractional part of a floating- point number; Also called the mantissa; Defines precision






40. 'Reconstructing' part of digital audio






41. Having a repeated succession of waves or curves as in a sound waveform






42. Difference in brightness between land and pit on a CD Physical Format






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






44. 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






45. Eight channel digital surround sound system by Dolby






46. 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






47. MPEG; Standardizing body of audio coding






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






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






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