dB review & New

Question 1

Explain boyle’s law

Answer 1

pressure and volume are inversely proportional (temperature constant)
ex: screaming in a helmet vs at a stadium - perceived as louder in the helmet vs an open field because of this

Question 2

Why are RETSPL numbers different?

Answer 2

need more sound from on the ear to get same measurement at ™ as you would with insert because of volume being less
amount of space bw transducer and ™ is less

Question 3

what is dB SL

Answer 3

difference between presentation level and the patient’s individual threshold
sensation level

Question 4

If you are using insert earphones and do not insert them deeply enough, will your measured thresholds be too large or too small? Explain your answer.

Answer 4

increases space if not in far enough so the thresholds would be too large (worse) because more sound was needed to get to the threshold
because more volume so you would have less spl and it would needed to be turned up to get a threshold

Question 5

ou measure a patient’s LDL (loudness discomfort level) at 1000 Hz using TDH 50 headphones. You find that it is 100 dB HL. Your hearing aid test box tells you that the maximum output of the hearing aid at 1000 Hz is 105 dB SPL. Does the hearing aid exceed the patient’s LDL?

Answer 5

dB SPL = dB HL + RETSPL
= 100 + 7.5
= 107.5
no, it doesn’t exceed it because the output is below the SPL

Question 6

he patient’s LDL at 500 Hz is 105 dB HL. The maximum output of the hearing aid at 500 Hz is 115 dB SPL. Does the hearing aid exceed the patient’s LDL?

Answer 6

= 105 + 13.5 =
= 118.5
Np, output is still lower than their SPL

Question 7

Why do we use dB HL?

Answer 7

so our normal thresholds all equal 0 and have a straight line

Question 8

how do we calculate dB HL

Answer 8

dB HL = dB SPL – RETSPL

Question 9

How do we calculate dB SPL

Answer 9

dB SPL = dB HL + RETSPL

Question 10

ONCE AN AUDIOMETER HAS BEEN CALIBRATED WITH A SPECIFIC HEADPHONE, CAN YOU USE A DIFFERENT HEADPHONE.

Answer 10

No, you cannot

Question 11

What is a transducer?

Answer 11

device that converts a particular form of input energy into different form of output energy

Question 12

what are the two basic types of transducers are utilized in audiologic testing

Answer 12

Acoustic –> electric energy
microphones
Electric –> acoustic energy
Earphones, loudspeakers, bone conduction vibrator

Question 13

If you have two people and one has tiny ear canal and one has large and you measure same threshold, who has the better hearing?
transducer is putting out 40 dB

Answer 13

as volume decreases, pressure increases
smaller ear canal gets more sound because sound pressure is more than the large canal and volume is smaller