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






2. The frequency range that is allowed through a filter






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






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






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






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






7. Series of dots and dashes representing the letters of the alphabet; Most common letters are represented by the shortest dots and dashes; Example of entropy coding






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






9. Defines the number of sample per second taken from a continuous signal to make a discrete signal; Governs the frequency response of digital audio






10. MPEG; Standardizing body of audio coding






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






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






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






14. 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






15. 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






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






17. 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






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






20. 8- in/8- out on one cable; 25- pin D- sub connector






21. 7.95 GB; SS/DL






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






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






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






25. Have odd numbered harmonics






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






27. Eight channel digital surround sound system by Dolby






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






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






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






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






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






33. A digital filter's time domain output sequence when the input is a single sample is input






34. 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






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






36. Sony and Philips optical disc format; Utilizes sigma delta DSD to offer higher resolution; 1- bit; 2.8224 MHz; 6-Channel






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






38. Found that aliasing was always a problem no matter how fast you sample; Less data recorded but more accurate; 2 samples per wave length.






39. Waveform of a pure tone showing simple harmonic motion






40. 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)






41. 1.) Bit Rate x Sample Rate (you'll get b/sec) 2.) Multiply by 60 if converting seconds to minutes 3.) Divide by 8 to convert bits to Bytes and get B/min 4.) Divide by 1 -024 to get KB/min and keep doing it until you get desired bit rate specification






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






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






44. 12cm plastic disc; 1.2mm thick; One- sided; Red Laser; 1.6 microns between tracks; 125 nanometer pits






45. Governs the frequency response of a digital system; The highest- frequency component that can be captured with a sampling rate; always 1/2 of sampling rate; Also called the limiting frequency






46. 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






47. 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






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






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






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