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






2. Represents the amplitude component of the digital sampling process; Technique of incrementing a continuous analog event into a discrete set of binary digits (bits)






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






4. 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)






5. Sample Rate x Bit Depth x # of Channels






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






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






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






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






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






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






12. Root Mean Square; Refers to taking the square root of all instantaneous amplitudes; Takes the average of those squares; (-6 Peak Level is approximately equal to -20 RMS)






13. 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






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






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






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






17. Measure of the amplitude of a longitudinal wave






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






19. 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






20. VBR; Most common & best data reduction technique; Codecs that encode data by determining how dense or sparse areas of the audio are; Can result in buffering issues






21. 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






22. 'Reconstructing' part of digital audio






23. 4.38 GB; SS/SL






24. 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






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






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






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






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






29. 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






30. Lossless Format; Can hold up to 25GB on a single- layer disc and 50GB on a dual- layer disc






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






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






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






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






35. Take up half as many bits (50%); Algorithm can keep same quality by lossing the stereo track






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






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






38. MPEG; Standardizing body of audio coding






39. CBR; Codecs encodes data at a constant rate regardless of density of the audio file






40. 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






41. 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






42. 'Capturing' part of digital audio; Never captures a signal perfectly






43. The continuous loss of signal strengths as a signal travels through a medium






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






45. 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






46. 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






47. 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






48. Pertaining to hearing or sound; Combination of the intensity of air pressure molecules with amplitude






49. Decibels Full Scale






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