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. Circuit that seizes voltage values with each tick of an A/D device's internal clock






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






3. 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






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






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






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






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






9. 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






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






11. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






12. 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)






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






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






15. The mathematics - algorithms - and the techniques used to manipulate signals after they have been converted to digital form






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






17. 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






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






19. Increases or decreases the digital signal so that the loudest sample is brought up to 0dBfs; Uses all bits from dynamic range and makes it even from track to track






20. 1.) Bit Rate x Sample Rate (you'll get b/sec) 2.) Multiply by 60 if converting seconds to minutes 3.) Divide by 8 to convert bits to Bytes and get B/min 4.) Divide by 1 -024 to get KB/min and keep doing it until you get desired bit rate specification






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






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






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






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






25. Unit of measurement that is equal to one millionth of a meter






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






27. 1st commercially successful AoE format for the transmission of digital audio - video - and control signals over 64- channel 100Mbps Ethernet networks






28. 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






29. EBU






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






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






32. 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






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






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






35. Mixing data and control characters in a single operation






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






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






38. 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






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






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






41. 4.38 GB; SS/SL






42. 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






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






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






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






46. 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






47. Sample Rate x Bit Depth x # of Channels






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






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






50. 12.33 GB; DS/ML