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. Computer program or device capable of encoding and/or decoding a digital data stream with the end result being a reduced file size






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






3. 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






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






5. 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






6. (Amplitude Based) Amplitude: Voltage; Quantization; Bit Depth; Quantization Intervals; Quantization Noise; [Signal:Quantization Noise Ratio]; Dither; Dynamic Range






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






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






9. 1st commercially successful AoE format for the transmission of digital audio - video - and control signals over 64- channel 100Mbps Ethernet networks






10. Number of bits used to represent the smallest unit of information in an audio file; Greater bit depth = better quality audio






11. 15.9 GB; DS/DL






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






13. Apple Lossless; Windows Media Lossless; DTS HD Master Audio; Dolby True HD; FLAC






14. Subtract place values from the decimal number and place ones or zeros in the correct places






15. The frequency range that is allowed through a filter






16. 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






17. Leaving space at beginning and ending of song for data crunching during mastering; Last step in mastering process






18. Sample Rate x Bit Depth x # of Channels






19. Digital (binary) measurements of how long each pulse is either on or off; Width of increasing voltage or decreasing voltage is assigned a 1 or 0 respectively






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






21. 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);






22. ADPCM; Pulse code modulation that produces a digital signal with a lower bit rate than standard PCM; Records only the difference between samples






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






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






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






26. 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






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






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






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






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






31. 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






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






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






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






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






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






37. 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






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






39. 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






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






41. A network communications protocol that specifies how machines will exchange data; Uses a broadcast system in which one machine transmits its message on the communication medium and the other machines listen for messages directed to them






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






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






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






45. Toshiba developed digital audio interface utilizes fiber optics as a transmission medium.






46. 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






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






48. 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






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






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