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. 8.75 GB; DS/SL






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






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






4. 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






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






6. ABR; Codecs that encode data by determining how dense or sparse areas of the audio are while also keeping bit rate within specified limits to avoid rebuffering






7. 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






8. Sample Rate x Bit Depth x # of Channels






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






10. 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.






11. Defines the number of sample per second taken from a continuous signal to make a discrete signal; Governs the frequency response of digital audio






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






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






14. 15.9 GB; DS/DL






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






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






17. Unit of measurement that is equal to one millionth of a meter






18. 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






19. 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






20. Cable used to transmit data; Inner cable is surrounded by a plastic insulator - which is surrounded by a wire mesh conductor that insulates the internal signal wire from external interference and an outer casing that functions as a ground






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






22. Have odd numbered harmonics






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






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






25. Channels are processed one at a time and the results are stored on multiple CPU buffers that alternately send data as DAW requests the data for playback; First few seconds are relayed to the buffer prior to processing and playback and it continuously






26. Measurement at regular intervals of the amplitude of a varying waveform (in order to convert it to digital form); There must be a minimum of 2 samples for each cycle in a waveform






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






28. 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)






29. Industry Standards: -6 dB Peak = -20 RMS Meter






30. Samples are duplicated and the playback sampling rate correspondingly increased; Significantly raises the Nyquist limit to a range well beyond human hearing; Processing 'pushes' the distortion resulting from quantization error into these higher frequ






31. 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






32. Governs the frequency response of a digital system; The highest- frequency component that can be captured with a sampling rate; always 1/2 of sampling rate; Also called the limiting frequency






33. The amount of energy at each wavelength






34. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






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






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






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






38. French mathematician that noted that any complex sound can be broken down into a series of component pure tones






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






40. 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);






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






42. The ability of a digital system to perform complex DSP without running into problems with overflow or loss of resolution






43. 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






44. Splits the input signal and mixes it with an analog copy so that no latency is present






45. 7.95 GB; SS/DL






46. Digital Word -> Series of Resistors (each with assigned charges) -> Sample- and-Hold Circuit -> Anti-Imaging Filter (Smoothing Filter) -> Reconstructed Sample






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






48. Data transmission protocol over which computer network traffic travels; Poorly suited to real- time transmission but numerous attempts have been made to harness the technology because of its flexible routing; Uses simple Cat5 cabling; Resists interfe






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






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