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. 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






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






3. 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






4. Mixing data and control characters in a single operation






5. In order to play multiple channels at one time data is buffered as read to disk; Latency happens between play command & beginning of playback






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






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






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






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






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






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






12. Eight channel digital surround sound system by Dolby






13. Waveform of a pure tone showing simple harmonic motion






14. The loudest point of a Full Scale system






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






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






17. 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






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






19. 4.38 GB; SS/SL






20. Based on psychoacoustics - these are the basis of frequency analysis for a perceptual codec;






21. As sample rate is increased more room is created for a smoother slope of the attenuation band because Nyquist limit extends well beyond range of hearing with each increase






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






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






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






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






26. 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






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






28. Sample Rate x Bit Depth x # of Channels






29. 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






30. 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






31. Snippets of time in which frequency analysis takes place in a perceptual codec






32. Only 2 digits used; The value of each place (ones - hundreds - etc.) are as follows from greatest to least: 128 - 64 - 32 - 16 - 8 - 4 - 2 - 1






33. 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






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






35. MPEG; Standardizing body of audio coding






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






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






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






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






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






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






43. 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






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






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






46. 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






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






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






49. Smallest interval measurable by a scientific instrument; Defined by bit rate (sample rate x bit depth)






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