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






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






3. 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






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






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






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






7. Digital Word -> Series of Resistors (each with assigned charges) -> Sample- and-Hold Circuit -> Anti-Imaging Filter (Smoothing Filter) -> Reconstructed Sample






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






9. 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






10. 1st commercially successful AoE format for the transmission of digital audio - video - and control signals over 64- channel 100Mbps Ethernet networks






11. 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






12. 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






13. 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






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






15. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






16. (AES/EBU); 110O - 2- channel balanced digital audio cable with an XLR connection; NOT a mic cable!!






17. 4.38 GB; SS/SL






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






19. As sample rate is increased more room is created for a smoother slope of the attenuation band because Nyquist limit extends well beyond range of hearing with each increase






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






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






22. 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)






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






24. 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.






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






26. In order to play multiple channels at one time data is buffered as read to disk; Latency happens between play command & beginning of playback






27. Roughly around 1 -130 ft/s






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






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






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






31. 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);






32. 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






33. The act of a frequency swinging back and forth with a steady - uninterrupted rhythm






34. Have odd numbered harmonics






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






36. MPEG; Standardizing body of audio coding






37. Number of bits per second processed when sampling sound; (Sampling Rate x Bit Depth) = Resolution






38. 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)






39. Process of building a complex tone by starting with the fundamental frequency and adding pure tone harmonics






40. Sony and Philips optical disc format; Utilizes sigma delta DSD to offer higher resolution; 1- bit; 2.8224 MHz; 6-Channel






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






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






43. 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






44. 15.9 GB; DS/DL






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






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






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






48. 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






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






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