Maico Round Hearing Loss Percentage Calculator
The Maico Hearing Loss Calculator is a cardboard
circular slide rule device that purports to calculate percent hearing loss.
(In truth, hearing loss is measured in decibels (dB) on an open-ended
logarithmic scale and thus cannot be expressed as a percentage.)
In order to determine the "percentage" of hearing
loss using the calculator, disks were rotated to set arrows under the
measured dB loss at 500 Hz, 1000 Hz and 2000 Hz. The total "percentage"
hearing loss is then read off on the scale at the bottom of the slide
rule.
The slide rule could also be used to calculate the
"percent" binaural impairment. |
