small, tiny question about hearing safety and spl regarding volume sliders.

[KonKossKang]

shuresrh440 came in the mail, expected less bass since everybody said these had none but suprised. have a small question about calculating spl in correlation the the volume slider of a mp3/aac player.

it says to prevent damage to ears dont do 120spl or 115spl for more than an hour or two.
the headphone at max volume is supposedly 105spl so if it the volume slider was at 80 percent it would be actually 84spl or does this depend on the device you use and whether or not you like to use your headphones connected to an amp?

is the indicated spl of headphones and speakers/monitors in general accurate when an external amp isn't involved?

 

[bandcoach]

without knowing the taper of the volume slider on your mp3 player there is no way to be certain: variable resistors are made with two tapers
- linear where the resistance is increased equally along the length of the resistor or
- logarithmically, where it it jumps according to the log principle
-- large sections for small increases initially then smaller and smaller as you proceed to the end



more importantly ignore the advice given and stick to 85dbspl for one hour at a time with a 1 hour rest period - this will ensure that you avoid fatigue and over-stimulation of any of the cilia in your cochlear