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






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






3. 'Capturing' part of digital audio; Never captures a signal perfectly






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






5. Decibels Full Scale






6. 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






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






8. Series of dots and dashes representing the letters of the alphabet; Most common letters are represented by the shortest dots and dashes; Example of entropy coding






9. 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






10. 16-Bit; 44.1 kHz; PCM; Stereo






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






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






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






14. The amount of energy at each wavelength






15. 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






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






17. 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






18. 4.38 GB; SS/SL






19. 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






20. Overtones that contribute to the timbre of a sound and make up a complex waveform's physical characteristics






21. 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






22. 'Reconstructing' part of digital audio






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






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






25. 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






26. A method of representing real numbers using a mantissa and an exponent






27. Snippets of time in which frequency analysis takes place in a perceptual codec






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






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






30. 8.75 GB; DS/SL






31. Industry Standards: -6 dB Peak = -20 RMS Meter






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






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






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






35. Same as 'aliasing'






36. Toshiba developed digital audio interface utilizes fiber optics as a transmission medium.






37. Sony sigma- delta modulation based technology that bypasses the decimation and interpolation steps found in PCM converters






38. Number or variable that represents the number of times the base of a power is used as a factor; Defines magnitude






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






40. 15.9 GB; DS/DL






41. 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






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






43. 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






44. 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






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






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






47. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






48. 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






49. AES






50. A sample- by- sample operation on two signals