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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. A frequency specified for a filter (digital or electronic) the marks the point at which the frequency content of a signal is altered +/- 3dB






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






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






4. Ratio of magnitude of the analytical signal to the magnitude of the background noise signal






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






6. 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






7. 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);






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






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






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






11. Six channel (five speakers and one subwoofer for bass) digital surround sound system by Dolby






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






13. Each bit in the bit depth is equal to a _____ increase in dynamic range






14. 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






15. How Loud (Y-Axis) & How Fast (X-Axis)






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






17. 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






18. 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






19. 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






20. More aggressive lossy data reduction techniques that require further manipulation of the stereo field; Examples are 'Intensity' & 'M-S'






21. 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






22. Have odd numbered harmonics






23. 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






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






25. 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






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






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






28. 1st commercially successful AoE format for the transmission of digital audio - video - and control signals over 64- channel 100Mbps Ethernet networks






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






30. 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






31. 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






32. 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)






33. Sample Rate x Bit Depth x # of Channels






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






35. 4.38 GB; SS/SL






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






37. ADAT Optcal; 8- in/8- out on two cables; Fiber- optic - TOSLINK connector






38. 12.33 GB; DS/ML






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






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






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






42. Data is transmitted over fiber optic lines; Uses a TOSLINK connecter instead of an RCA type; Can transmit multi- channel audio; Not susceptible to ground hum and loops; Able to support far higher rates of data transfer over greater distances than coa






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






44. Most significant lossless coding technique in current use; Measure of disorder in which long strings of data are represented by short symbols and uses the shortest symbols to represent the most common repetitive audio data maximizing data reduction






45. 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






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






47. 8.75 GB; DS/SL






48. When recording you want the smallest buffer available; When mixing you want the largest buffer available






49. Measure of the amplitude of a longitudinal wave






50. 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