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. 8.75 GB; DS/SL






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






3. 16-Bit; 44.1 kHz; PCM; Stereo






4. 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.






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






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






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






8. Increases D/A sample rate from nominal rate to oversampling rate by turning series multi- bit PCM samples into 1- bit samples; (ex. => 44.1kHz sample rate converted to 2.8MHz and simultaneously converts multi- bit samples to 1- bit); Low Pass Filter






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






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






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






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






13. Same as 'aliasing'






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






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






16. 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






17. 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)






18. Method of representing an acoustic quantity with a series of binary numbers; Can have only specific individually distinct values






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






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






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






22. 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






23. 12.33 GB; DS/ML






24. 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






25. Allowance of noise floor below that which is required for the final product






26. 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






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






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






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






30. 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






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






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






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






34. 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






35. MPEG; Standardizing body of audio coding






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






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






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






39. 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)






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






41. 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






42. 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






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






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






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






46. Describes various optical disc characteristics including the size and shape of the disc - the size of pits - the speed at which the disc spins - and a multitude of aspects regarding the specifications of the player itself






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






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






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