Test your basic knowledge |

Microphones Theory

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. Close mic placement can help guard again bleed from other instruments and takes advantage of proximity effect; Center of cone = Brighter; Outside of cone = Darker; Reflections can create phase issues (can be reduced by putting the cabinet at an angle






2. Microphone with 4 large diaphragm condenser capsules; 3 bidirectional and 1 omni; Can be combined to make any polar pattern.






3. Adds two outer right and left rear facing mics to a Decca tree for surround sound depth.






4. Utilized primarily on condenser and ribbon mics to isolate it from vibrations that might otherwise be transmitted to the microphone through the mic stand.






5. Never store mic in a damp place; Keep dirt & dust away from the mic; Never 'pop' test the mic; Check if a mic is working by lightly scratching the grill.






6. Cable wrapping method that reduces interference and makes it easier to unravel the cable.






7. Used by government agencies to determine safe sound exposure levels (in dB) over a period of time; 85 - 90 dB = 16 hrs. of safe exposure time at 85 dB; Decreases to 8 hrs. of safe exposure time at 90 dB.






8. Mics in which sound waves vibrate a piezoelectric crystal that generates a varying voltage.






9. A gradual - continuous decrease in low frequency response.






10. Microphone consisting of two parallel metal plates - each holding an opposing charge (+ or -) and thus creating a capacitor to induce an electrical charge as sound waves move the diaphragm; Require a solid- state or tube preamplifier.






11. Overall measurement close to the overall sound level in frequency response charts.






12. Voltage applied to piezoelectric material will cause it to deform or change shape; NO PHANTOM POWER!






13. The first cardioid pattern dynamic microphone.






14. Commonly utilize large diaphragm dynamic mics.






15. Pure polar pattern with which the microphone is equally sensitive in all directions; Great for capturing ambiance or room reverb.






16. One of the oldest mics; Diaphragm mounted on & compresses cup of tiny granules of carbon (100 microns big) that increase current flow when compressed by sound waves and vary electrical current; Also called Resistance Mics;






17. Tube with ports down the side with the mic capsule at the bottom; Sounds entering the tube from on - axis interact inside the tube with the sounds coming in through the side ports - an interfere with each other in such a way as to partially cancel of






18. Part of a mic stand that the mic stands on.






19. The measuring device used for loudspeaker room response testing.






20. Often look like large diaphragm studio mics; Talk or sing into the side of the microphone.






21. Mounts on a single stand to provide for adjustable spacing and angling between mics.






22. A 3- mic array using omni mics with left - right and center placement; Center is placed about 5 ft. closer to the source to eliminate 'holes' in the middle and the center levels are reduced for an even sound; Forms a triangle.






23. Keep in proper case; Never disassemble shockmounts






24. An instrument for detecting sound transmitted through water commonly manufactured using ceramic piezoelectric material.






25. Condenser; Cardioid; End Address; 48V Required; Manufactured by AudioTechnica; Switchable 80 Hz Hi-Pass Filter; Ideal for professional recording and critical applications in broadcast.






26. An electromagnetic microphone - in which a thin - corrugated ribbon is suspended within a high magnetic flux field; Excellent transient response due to the small amount of acoustic energy required to move diaphragm.






27. Configured to simulate the spacing and directivity of human hearing; Box shape with two 'ears' on each side.






28. The lowest - and usually most intense - frequency of a complex sound; Most often perceived as the sound's basic pitch.






29. Big + & - (More front with less opposite rear)






30. Digital device used to Fourier Forms; Used to measure the specific number of sine waves in a specific frequency in a specific setting.






31. Tube microphone capable of SPL's over 140dB.






32. Condenser; Cardioid; End Address; 48V Required; Manufactured by Neumann; Consists of three compact miniature microphones; Has a gentle rise at about 9 kHz that provides tonal balance that is fresher and livelier.






33. Timing difference between two waves; Waves interfere cancelling each other out and altering frequency response; Measured in degrees; Can be caused by reflections of sound waves; Can be reduced by putting cabinet or amp at an angle.






34. Three or more microphones working together to capture a stereo or surround image of the sound source.






35. E = Blv - e - Electromotive Force (in volts) - B - is the magnetic field strength - l - is the length of the conductor - v - is the velocity of the conductor moving through the magnetic field






36. Causes an increase in low frequency response as one gets closer to the source.






37. The attachment that holds a microphone in place on the mic stand; Comes in various shapes - sizes - and applications.






38. - Omnidirectional: 1 - Cardioid: 1.7 - Supercardioid: 1.9 - Hypercardioid: 2 - Bidirectional: 1.7






39. Small coil of wire wrapped around the plastic or aluminum diaphragm of a dynamic microphone.






40. Demonstrated the first stereophonic transmissions via the Theatrophone in 1881.






41. Changes in air pressure from the front or the back can cause polarity cancellation; Sides have good rejection; Natural polar pattern is bidirectional.






42. Mics placed in front of an instrument or ensemble (in a left/right fashion) to obtain an overall stereo image; Sound more open and natural; Weaker center image than X/Y; Great for creating background sounds that will blend in with foreground sounds.






43. Determined by: Ribbon Thickness (about 3 to 6 microns); Corrugations/Inch; Tension of the Ribbon.






44. Extremely narrow area of sensitivity in front with extended reach; Also has multiple lobes which vary in position with frequency; Not made from combining pure patterns - but created by using an interference tube.






45. Dynamic; Cardioid; End Address; Manufactured by Shure; Popular musicians' choice due to its sturdy construction and ability to work well with instruments that produce high sound pressure levels.






46. Very robust and durable; Used in telephones until 1990's; Currently finds applications for military use.






47. Proportional to: Magnetic field strength; Length of the conductor; Velocity of conductor moving through the magnetic field.






48. Coincident pairing of two bidirectional mics that make a pattern of crossing Figure 8's.






49. First microphone invented by Georg Neumann






50. The head or top of the guitar where the tuning pegs are located.