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. AAC (Advanced Audio Coding); MP3; RA; WMA; OGG Vorbis; Dolby Digital/AC-3; DTS; ADPCM






2. 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






3. The loudest point of a Full Scale system






4. Eight channel digital surround sound system by Dolby






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






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






7. Based on Full Scale (dB/FS); -6dB represents a loss of one bit so account for this when calculating






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






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






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






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. Low Pressure; Part in a longitudinal wave where the particles are spread apart






13. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






14. 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






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






16. CBR; Codecs encodes data at a constant rate regardless of density of the audio file






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






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






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






20. 15.9 GB; DS/DL






21. 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






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






23. A drive that can read and write on optical media that hold up to 50 GB on two layers; 24- bit/96 kHz for 8-Channel; 24- bit/192 kHz for 6-Channel






24. 8.75 GB; DS/SL






25. A situation where a calculated value cannot fit into the number of digits reserved for it






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






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






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






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






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






31. Inner ear component that attaches to the stapes and helps to decrease the amplitude of vibrations; Causes the masking phenomenon






32. 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






33. Signal voltage is relayed to a register from sample- and - hold circuit; Holds reference frequencies in binary form that decrease in value; Finds approximated value & assigns binary number accordingly






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






35. 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.






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






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






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






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






40. The frequency range that is allowed through a filter






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






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






43. Measure of the amplitude of a longitudinal wave






44. A digital filter's time domain output sequence when the input is a single sample is input






45. 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






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






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






48. Amplitude meter that takes the square root of all instantaneous amplitudes and averages them to find a mean and squares that value; Useful with particularly complex waveforms






49. 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






50. If a signal is sampled at a rate higher than twice the highest significant signal frequency and at evenly spaced intervals - then the samples contain all the information of the original signal