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. Computer program or device capable of encoding and/or decoding a digital data stream with the end result being a reduced file size






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






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






4. Measure of the amplitude of a longitudinal wave






5. 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






6. Governs the frequency response of a digital system; The highest- frequency component that can be captured with a sampling rate; always 1/2 of sampling rate; Also called the limiting frequency






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. Channels are processed one at a time and the results are stored on multiple CPU buffers that alternately send data as DAW requests the data for playback; First few seconds are relayed to the buffer prior to processing and playback and it continuously






9. EBU






10. 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






11. 1st commercially successful AoE format for the transmission of digital audio - video - and control signals over 64- channel 100Mbps Ethernet networks






12. 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






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






14. 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)






15. Take up half as many bits (50%); Algorithm can keep same quality by lossing the stereo track






16. Anytime bit depth is reduced the gap gets bigger so more dithering is required






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






18. Circuit that interprets the meaning of the symbols as they were chosen and arranged by the encode






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






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






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






22. 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






23. 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






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






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






26. 8.75 GB; DS/SL






27. 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)






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






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






30. DAW's and software must buffer when converting or bouncing and this latency can add up if not monitored






31. 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






32. MPEG; Standardizing body of audio coding






33. 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






34. Father of modern information theory; Solidified the Nyquist Theory by adding the concept that bits per second (binary representation of audio signals) must be at equal intervals to accurately represent data






35. Visual graph that shows how loud a sound is at different frequencies






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






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






38. Digital and analog processing capability is combined on a single microchip allowing for 1- bit resolution at high sample rates






39. The elapsed time it takes for a packet of data to arrive at its destination; Lagging or pause of an audio signal as digital processing occurs; Can be managed utilizing several forms of 'audio monitoring'






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






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






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






43. French mathematician that noted that any complex sound can be broken down into a series of component pure tones






44. 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






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






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






47. Improper (false) sampling of high frequencies that cause much lower frequencies to be produced when the audio is reconstructed; Foldover happens at higher frequencies as harmonics reach levels that exceed the Nyquist limit.






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






49. Subtract place values from the decimal number and place ones or zeros in the correct places






50. 'Reconstructing' part of digital audio