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






2. HD Audio format; Lossless Compression; 24- bit/96 kHz; 5.1 Surround or 24- bit / 192 kHz stereo sound






3. 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






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






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






6. The frequency above or below which attenuation begins in a filter circuit






7. EBU






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






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






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






11. The frequency range that is allowed through a filter






12. 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






13. 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






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






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






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






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






18. 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.






19. 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.






20. Ultra low- latency - 512- channel (on a gigabit network) - less flexible AoE format; Routed like audio cables...not network cables






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






23. 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






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






25. Very quiet digital amplifier that produces a series of output pulses with the audio signal coded the same as the width of the output pulses; Pulses are used to represent wave forms and are either on or off; Intense signals have long pulses with short






26. 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






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






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






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






30. 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






31. 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'






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






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






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






35. Perceptual coding technique that uses louder sounds of a similar frequency to decide what information is to be saved during data reduction






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






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






38. 8- in/8- out on one cable; 25- pin D- sub connector






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






40. Number of bits used to represent the smallest unit of information in an audio file; Greater bit depth = better quality audio






41. Same as 'aliasing'






42. Contains all even and odd harmonics associated with a fundamental tone - making it a rich source for modeling other sounds; Amplitude of each overtone decreases exponentially as a ratio of the harmonic's frequency to that of the fundamental






43. 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






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






45. The art of deciding where to place a processor in signal flow based on how that processor will be influenced by the other processors in the path






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






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






48. Process that begins with a fast FFT analysis of the spectra of two input signals - then the multiplication of like frequencies - and IFFT to finalize the process






49. 12.33 GB; DS/ML






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