Effects of Different Stimulus Types
Experiments have been carried out to see the different masking effects when using a masker which is either in the form of a narrow band noise or a sinusoidal tone.
When a sinusoidal signal and a sinusoidal masker (tone) are presented simultaneously the envelope of the combined stimulus fluctuates in a regular pattern described as beats. The fluctuations occur at a rated defined by the difference between the frequencies of the two sounds. If the frequency difference is small then the sound is perceived as a periodic change in the loudness of a single tone. If the beats are fast then this can be described as a sensation of roughness. When there is a large frequency separation, the two components are heard as separate tones without roughness or beats. Beats can be a cue to the presence of a signal even when the signal itself is not audible. The influence of beats can be reduced by using a narrowband noise rather than a sinusoidal tone for either signal or masker.
Read more about this topic: Simultaneous Masking
Famous quotes containing the words effects of, effects, stimulus and/or types:
“Some of the greatest and most lasting effects of genuine oratory have gone forth from secluded lecture desks into the hearts of quiet groups of students.”
—Woodrow Wilson (1856–1924)
“Like the effects of industrial pollution ... the AIDS crisis is evidence of a world in which nothing important is regional, local, limited; in which everything that can circulate does, and every problem is, or is destined to become, worldwide.”
—Susan Sontag (b. 1933)
“Decisive inventions and discoveries always are initiated by an intellectual or moral stimulus as their actual motivating force, but, usually, the final impetus to human action is given by material impulses ... merchants stood as a driving force behind the heroes of the age of discovery; this first heroic impulse to conquer the world emanated from very mortal forces—in the beginning, there was spice.”
—Stefan Zweig (18811942)
“If there is nothing new on the earth, still the traveler always has a resource in the skies. They are constantly turning a new page to view. The wind sets the types on this blue ground, and the inquiring may always read a new truth there.”
—Henry David Thoreau (1817–1862)