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. 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)






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






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






4. 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






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






6. 8- in/8- out on one cable; 25- pin D- sub connector






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






8. MPEG; Standardizing body of audio coding






9. Have odd numbered harmonics






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






11. 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






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






13. 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






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






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






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






17. 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)






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






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






20. Only 2 digits used; The value of each place (ones - hundreds - etc.) are as follows from greatest to least: 128 - 64 - 32 - 16 - 8 - 4 - 2 - 1






21. A drive that can read and write on optical media that hold up to 50 GB on two layers; 24- bit/96 kHz for 8-Channel; 24- bit/192 kHz for 6-Channel






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






23. 4.38 GB; SS/SL






24. The frequency range that is allowed through a filter






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






26. 1st commercially successful AoE format for the transmission of digital audio - video - and control signals over 64- channel 100Mbps Ethernet networks






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






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






29. 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






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






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






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






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






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






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






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






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






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






39. Measure of the amplitude of a longitudinal wave






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






41. Decibels Full Scale






42. 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)






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






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






45. 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






46. 15.9 GB; DS/DL






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






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






49. 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






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