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






2. 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






3. Have odd numbered harmonics






4. 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






5. Mixing data and control characters in a single operation






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






7. Cable used to transmit data; Inner cable is surrounded by a plastic insulator - which is surrounded by a wire mesh conductor that insulates the internal signal wire from external interference and an outer casing that functions as a ground






8. 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.






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






10. Improper (false) sampling of high frequencies that cause much lower frequencies to be produced when the audio is reconstructed; Foldover happens at higher frequencies as harmonics reach levels that exceed the Nyquist limit.






11. Digital (binary) measurements of how long each pulse is either on or off; Width of increasing voltage or decreasing voltage is assigned a 1 or 0 respectively






12. 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






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






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






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






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






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






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






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






20. 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






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






22. The amount of energy at each wavelength






23. Eight channel digital surround sound system by Dolby






24. 12.33 GB; DS/ML






25. Waveform of a pure tone showing simple harmonic motion






26. 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)






27. Decibels Full Scale






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






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






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






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






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






33. 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






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






35. 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






36. Used when the reference pressure of a sound is 20 microPa (0.00002); Sound Pressure Level; Measure of amplitude






37. The frequency above or below which attenuation begins in a filter circuit






38. 16-Bit; 44.1 kHz; PCM; Stereo






39. 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






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






41. Method used in digital recording and reproduction in which a signal is sampled at various points and the resulting value is translated into binary numbers






42. 7.95 GB; SS/DL






43. 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






44. 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






45. 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






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






47. 'Reconstructing' part of digital audio






48. 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






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






50. Voltage -> Dither -> Anti-Aliasing (Low Pass Filter) -> Sample & Hold Circuit -> Successive Approximation/Quantizer --) 100111010 (PCM Audio File)