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






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






3. 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






4. 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






5. 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






6. 'Reconstructing' part of digital audio






7. 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






8. High channel count; 64 channels on one cable; Coaxial cable with BNC connector or fiber optic with ST1 connector






9. 15.9 GB; DS/DL






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






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






12. 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






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






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






15. Occurs as data is assembled into meaningful bits or information and as left & right channels are separated






16. 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






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






18. Measure of the amplitude of a longitudinal wave






19. 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






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






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






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






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






24. 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






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






26. 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






27. Sample Rate x Bit Depth x # of Channels






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






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






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






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






32. RAM holds in memory audio data before it is transferred to the memory controller; Certain amount of data is processed before large amounts of data are streamed to prevent latency






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






34. Algorithm uses matrix of a mid/side microphone pair to determine a side signal & that signal is reduced then distributed as code in stereo






35. 7.95 GB; SS/DL






36. 1st commercially successful AoE format for the transmission of digital audio - video - and control signals over 64- channel 100Mbps Ethernet networks






37. 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






38. Method of representing an acoustic quantity with a series of binary numbers; Can have only specific individually distinct values






39. Reduces A/D sample rate from the oversampled rate to nominal rate by turning series of one- bit samples into a series of multi- bit PCM samples; (ex. => 2.8MHz sample rate converted to 44.1kHz and simultaneously converts 1-Bit samples to multi- bit);






40. 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






41. Pertaining to hearing or sound; Combination of the intensity of air pressure molecules with amplitude






42. 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.






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






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






45. Mixing data and control characters in a single operation






46. Waveform of a pure tone showing simple harmonic motion






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






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






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






50. Decibels Full Scale