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. 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)






2. 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






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. 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






5. 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






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






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






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






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






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






11. 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






12. EBU






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






14. 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






15. The act of a frequency swinging back and forth with a steady - uninterrupted rhythm






16. Eliminates frequencies above the Nyquist limit from becoming samples; Occurs prior to quantization






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






18. Anytime bit depth is reduced the gap gets bigger so more dithering is required






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






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






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






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






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






24. Six channel (five speakers and one subwoofer for bass) digital surround sound system by Dolby






25. Data reduction technique that selectively removes original information in order to significantly reduce the file size; Some data is lost; Files can be reduced up to 99% in size (90% with no perceived sound quality loss); Bit rate effects the perceive






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






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






28. Describes acceptable data - performances both offered and essential for a disc player - and the complete user experience






29. 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.






30. 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






31. 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






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






33. CobraNet; EtherSound; Dante; AVB (currently under development)






34. 15.9 GB; DS/DL






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






36. Fractional part of a floating- point number; Also called the mantissa; Defines precision






37. 8- in/8- out on one cable; 25- pin D- sub connector






38. Specific set of instructions for carrying out a data reduction technique that determines how to 'save' binary data information efficiently






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






40. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






41. 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)






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






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






44. 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






45. 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






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






47. 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






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






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






50. 12.33 GB; DS/ML