Propagated change or disturbance in the density, and there fore in the pressure, of an elastic medium?
Sound waves that travel in expanding spheres (or shells) in the same direction as the vibrating body?
The two chief sources of sound?
A vibrating body
throttled or modified air stream
A pure tone with uncomplicated alternations of compression and rarefaction?
The vertical axis of a Sine Wave shows what?
Amplitude or Loudness
The horizontal axis of a Sine Wave shows?
The number of times a vibrating body completes a pattern of complete cycles of compression and rarefaction per second are called?
Time required for one complete cycle of compression and rarefaction?
Graphically describes the intensity of the energy a vibrating body delivers?
Speed of sound?
Sound waves travel at 1,100 ft per second
Distance covered by one complete cycle of a wave?
What effects does temperature have on sound?
The higher the temp the faster sound travels
Sounds reflecting, leaving a persistence of sound after the sound ceases?
Sound reflection heard separately from the original sound?
Difference between the actual pressure at any point in a sound wave at any instant, and the average pressure at that point?
When a sound wave begins at 0° or ends at 360°
When the sound reaches one ear before the other, slightly out of phase we determine?
What is it when two tones of almost identical frequency combine and you hear a noticeable increase and decrease in the tone?
Complex sounds that repeat themselves slowly over time like music and speech?
Complex sounds without a period or pattern?
The measured force or power of the pressure changes of sound?
Compares the loudness level of a sound at one frequency to the same loudness at another frequency?
A subjective unit of loudness that uses the average normal judgments of loudness going up frequency, not across?
The physical measurement in Hz, or cycles per second, related to the listeners interpretation of pitch?
Pitch is measured in?
Relatively narrow bands of nearly the same frequency become one pitch, there are 22 narrow bands in the mid frequencies that are called?
Critical bands of frequency can be come widened and impaired in the cochlea, giving the hearing impaired person?
Reduced Frequency Resolution
The involuntary tendency of a speaker to raise ones voice in the presences loud noise to enhance the audibility of their voice?
The base frequency of an individuals speech, for men it's between 120-250Hz and women it's between 210-325Hz?
In speech, vocal folds setup secondary vibrations which reinforce some frequencies are called?
The reinforced frequencies of speech are called?
Speech requires a balance between vowels, consonants and this to be intelligible, the moving of energy peaks from one frequency to another?
When fitting a hearing instrument, either the instrument itself or an earmold blocks off the ear canal causing a loss of ear resonance?
The fitting method of dividing, adding or multiplying factors, based on audiometric hearing loss at each frequency?
The fitting method of comparing one product, slope, frequency, output or other measurement with another is?
This Comparative Fitting Method emphasizes speech discrimination scores in quiet and noise, and aided SRT and tolerance thresholds?
This Comparative Fitting Method involved providing enough gain at each frequency to correct the pure tone sensitivity to normal?
Mirroring the Audiogram
This Comparative Fitting Method finds the MCL for a 1000Hz tone, the finds the intensity required to match this loudness at specific frequencies?
Equal Loudness Contours
This Comparative Fitting Method finds the midpoint of the dynamic range between 1000 - 4000Hz, using the difference between UCL-SRT?
This Comparative Fitting Method measures threshold, MCL and UCL at each frequency, using a damped wave train in SPL instead of pure tones?
This Prescriptive Fitting Method uses a formula to give a practical general guideline, suggesting the gain requirements to reach MCL through the HI at approximately one-half the pure tone threshold?
Half Gain Formula
This Prescriptive Fitting Methodn uses 1/3 of the pure tone thresholds minus 5dB at 250Hz and 3dB at 500Hz
This Prescriptive Fitting Method uses 1/3 the pure tone thresholds at 500Hz and 1/2 at 1000-4000Hz?
This Prescriptive Fitting Method selects the frequency-gain characteristics of the instrument so amplified conversational speech falls in the middle of the dynamic range?
Skinner Procedure for Ski-Slope Losses
This Prescriptive Fitting Method uses UCL and instrument correction factors to amplify louder speech sounds without distortion
When the head blocks sound arriving from the unamplified side, causing high frequency attenuation?
Head Shadow Effect
When the ear loses is ability to discriminate words because of the prolonged lack of use of amplification?
This type of Fitting uses a body worn hearing instrument and a Y-cord connected to a receiver in each ear?
This type of fitting uses a complete hearing instrument on the better ear and a second microphone on the non-functional ear?
Seven reasons an ear can not be aided?
Loss greater then the maximum amplification of the instruments
Severe or Profound Mixed Loss
Abnormally small dynamic range
Abnormally low UCL
Very poor discrimination that degrades the better ear
Ear under medical treatment
Doctor recommends that amplificaton be avoided
The effect caused by when an aid is in place and the patient perceives their own voice being louder, scratchy and unpleasant?
In a hearing instrument what does the microphone do?
Receives sound and transduces acoustic energy into electrical energy
In a hearing instrument what does the receiver do?
Receives the electrical energy from the receiver and transduces it back to acoustic energy.
The flow of electrons from atom to atom is called?
Electrical current is measured in what?
Electrons move freely through materials like copper, gold, silver and aluminum which are?
This device only allows electrons to move under certain conditions such as if heat, light or an electrical field are applied?
In a Hearing Instrument the great the flow of current produces more?
Volume and Intensity
The Hearing Instrument battery provides the power source to increase the flow of current. The strength of the battery is measured in?
A battery generates this which always flows in on direction to the positive terminal?
This type of current is created when electrons flow to the positive terminal until it is no longer positive. The side that was negative lost all of its electrons making it positive causing the electrons to flow back?
This restricts electron movement causing electrical friction between moving electrons and the stationary atom, which causes heat?
Electrical resistance is measured in?
Electrical current or sound pressure is directly proportional to what?
Size of the voltage (battery)
Electrical current is inversely proportional to the?
Resistance of a wire or tubing (larger wire/tube less current)
Resistance is directly proportional to?
Length of a wire/tubing
Resistance caused by a longer wire/tubing emphasizes which frequencies?
Resistance caused by a shorter wire/tubing emphasizes which frequencies?
Resistance is inversely proportional to its?
Cross-sectional area (width); Thicker wires or wider tubes offer less resistance
What effect does a capacitor have on frequency?
Passes the high frequencies
Blocks the low frequencies
What effect does an inductor have on frequency?
Passes the low frequencies
Blocks the high frequencies
The type of microphone used in an HI is a permanently polarized material, that has a wide, flat frequency response, with excellent sensitivity and durability?
The Electret Microphone is what type of directional microphone?
These increase the strength of the electrical impulses from the microphone?
This HI feature is a magnetic induction coil that responds to magnetic leakage from phones or induction loop systems?