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






2. Twice as many samples as the highest frequency at minimum; Sampling rate totally controls frequency response






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






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






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






6. 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






7. Measure of the amplitude of a longitudinal wave






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






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






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






11. Eight channel digital surround sound system by Dolby






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






13. 1.) Taking a series of evenly- spaced measurements 2.) Signal contains no frequency components higher than half the sample rate






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






15. 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






16. The amount of energy at each wavelength






17. Represents the amplitude component of the digital sampling process; Technique of incrementing a continuous analog event into a discrete set of binary digits (bits)






18. 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






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






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






21. Measuring equipment in A/D conversion that processes voltage and provides a value for that voltage






22. 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






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






24. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






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






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






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






28. 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






29. Method used in digital recording and reproduction in which a signal is sampled at various points and the resulting value is translated into binary numbers






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






31. 8.75 GB; DS/SL






32. Multi-Bit Words; (Pulse Code Modulation)






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






34. Have odd numbered harmonics






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






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






37. 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.






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






39. 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






40. Allows for an internal sample rate at multiples of the input and output rates; Alleviates the need for steep 'brickwall' filters; Often combined with internal '1- bit' processing; Increases smoothing effect






41. Data reduction technique that does not effect quality of original audio; No effect on original quality; Typically around 50% reduction; Exact reconstruction of digital code for the audio signal






42. 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






43. Accuracy with which an electronic system reproduces the sound or image of its input signal






44. EDL; Final list of samples used in the audio editing process; Identified by time code






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






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






47. 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






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. Each bit in the bit depth is equal to a _____ increase in dynamic range






50. Removes high frequency images and noise and smoothes the stair case output coming from of the sample and hold circuit; Also called a SMOOTHING FILTER