White noise generator, Filters, amplifier, speaker

 

Code Number: 3C50.55

Demo Title: Noise Generator and Filters

Condition: Excellent

Principle: Noise Generators, Selective Filters

Area of Study: Oscillations & Acoustics

Equipment: 

White noise generator, Filters (Glass and Cardboard), amplifier, speaker, special vocal filters.

Procedure:

The filters fit over the speaker and will eliminate certain frequencies when the unit is driven with a white or pink noise generator.  

Vocal sounds can be demonstrated using the special filters over a small speaker driven with white noise.  Sounds from the filters should approximate AH, EE, EH, OO, and OH.  

Instead of the speaker and white noise, you can also drive the special filters with the duck calls.  Insert the duck call into the filter adapter and blow so that a single vibrating tone is produced and then modified with the filter.  

References:

  • Ron Hipschman, "Vocal Vowels", Exploratorium Cookbook III, p. 194.1 - 194.5.
  • Richard Berg, "Another Resonance Tube Demonstration", PIRA News, Vol. 8, No. 3, p. 32.