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






2. The elapsed time it takes for a packet of data to arrive at its destination; Lagging or pause of an audio signal as digital processing occurs; Can be managed utilizing several forms of 'audio monitoring'






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. 15.9 GB; DS/DL






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






6. 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






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






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






9. Deviation from a normal - steady pulse or tick of a clock that contributes to misrepresentation of a signal; Result of small timing irregularities that become magnified during the transmission of digital signals as the signals are passed from one dev






10. 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






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






12. Built into DAWs; Bits are added when signals are mixed together to avoid clipping






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






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






15. 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






16. 1st commercially successful AoE format for the transmission of digital audio - video - and control signals over 64- channel 100Mbps Ethernet networks






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






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






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






20. EBU






21. 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






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






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






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






25. Measures the highest levels of a signal being recorded or mixed; Monitors for clipping - which occurs at 0dBFS); Does not always reflect perceived volume of signal






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






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






28. 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






29. 12.33 GB; DS/ML






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






31. AES






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






33. Overtones that contribute to the timbre of a sound and make up a complex waveform's physical characteristics






34. Allowance of noise floor below that which is required for the final product






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






36. 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






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






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






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






40. Process of building a complex tone by starting with the fundamental frequency and adding pure tone harmonics






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






42. 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






43. 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






44. 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






45. Having a repeated succession of waves or curves as in a sound waveform






46. The difference between the analog value and the approximated digital value due to the 'rounding' that occurs while converting the analog signal to digital






47. 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






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






49. Measure of the amplitude of a longitudinal wave






50. 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