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






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






3. Snippets of time in which frequency analysis takes place in a perceptual codec






4. 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






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






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






7. 16-Bit; 44.1 kHz; PCM; Stereo






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






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






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






11. 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






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






13. EDL; Final list of samples used in the audio editing process; Identified by time code






14. 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






15. Discrete incremental distinctions made between the value of one sample and the next; Breaks down bit depth into a series of evenly spaced intervals






16. Decibels Full Scale






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






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






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






20. Serial Copy Management System; main difference between AES3 & S/PIDF






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






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






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






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






25. A method of representing real numbers using a mantissa and an exponent






26. MPEG; Standardizing body of audio coding






27. 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






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






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






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






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






33. 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






34. Have odd numbered harmonics






35. 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






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






37. Reference voltage determined by summing the voltage values of a predetermined number of previous samples; Numbers of 1 in row = waveform peak; Numbers of 0 in row = waveform trough; Basis of Sony's Direct Stream Digital (DSD)






38. A situation where a calculated value cannot fit into the number of digits reserved for it






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






40. Branch of psychology concerned with the subjective perception of sound






41. (Time Based) Frequency: Aliasing; Anti-Aliasing Filter; Sample Rate; Nyquist Limit






42. Describes various optical disc characteristics including the size and shape of the disc - the size of pits - the speed at which the disc spins - and a multitude of aspects regarding the specifications of the player itself






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






44. More accuracy in low amplitudes and less in higher amplitudes






45. 12.33 GB; DS/ML






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






47. The frequency range that is allowed through a filter






48. 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






49. 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






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