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






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






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






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






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






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






7. 'Reconstructing' part of digital audio






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






9. Specific set of instructions for carrying out a data reduction technique that determines how to 'save' binary data information efficiently






10. 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






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






12. 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)






13. A network communications protocol that specifies how machines will exchange data; Uses a broadcast system in which one machine transmits its message on the communication medium and the other machines listen for messages directed to them






14. The more bits allocated during quantization - the more accurate the measurement






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






16. 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






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






18. The elapsed time it takes for a packet of data to arrive at its destination; Lagging or pause of an audio signal as digital processing occurs; Can be managed utilizing several forms of 'audio monitoring'






19. 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






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






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






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






23. 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)






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






25. Describes acceptable data - performances both offered and essential for a disc player - and the complete user experience






26. Visual graph that shows how loud a sound is at different frequencies






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






28. 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






29. The set of rules that computers use to move files from one computer to another on an internet






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






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






32. Single- pin RCA cable or fiber- optic TOSLINK connector used for digital transfer; 75O coaxial - 2- channel unbalanced; 'Consumer' format of AES3






33. 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






34. 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)






35. Sony sigma- delta modulation based technology that bypasses the decimation and interpolation steps found in PCM converters






36. The difference between the analog value and the approximated digital value due to the 'rounding' that occurs while converting the analog signal to digital






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






38. 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






39. Mixing data and control characters in a single operation






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






41. EBU






42. 4.38 GB; SS/SL






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






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






45. 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






46. Apple Lossless; Windows Media Lossless; DTS HD Master Audio; Dolby True HD; FLAC






47. A time regulator that makes all samples and bits to align when working with interconnected digital devices; Basically a signal that all of the digital devices refer to when operating.






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






49. 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






50. The process of reducing the space required to store data by efficiently encoding the content.