I've been contacted by a young person in Hungary who is
concerened that his music listening habits may be damaging
his hearing. He saw that my Daqarta software has a built-
in SPL meter feature, and he wanted to know how to use it
to measure the headphone level of his music, so he could
keep it under 80 dB SPL.
Unfortunately, he says he can't afford a calibrated
microphone, which would of course be needed for any SPL
measurements.
Since this is just for "casual" purposes, not research,
etc, he'd probably be happy with some sort of rule-of-thumb
metric... but I don't know of any. I'm thinking here of
non-technical things like they recommend for aerobic
exercise, such as "walk fast enough so that you can just
barely carry on a conversation"... only for hearing.
(Anyone?)
One problem is that I can't think of any household sounds
with a standard loudness. Another is that if he already
has some PTS he would get false assurance that his
listening levels were not too loud.
So my question for the group is about using TTS. The
beauty of this is that it requires no absolute calibration.
He could measure his threshold at some specified frequency
in the morning before he starts his music listening, and
record the level in dB relative to full scale (whatever it
might actually be), then repeat it after listening and take
the difference. He can use Daqarta to do this for free.
I think if he finds *any* shift it means his music is too
loud, but the converse is probably not true... especially
if there is already some PTS, which would presumably reduce
the amount of TTS. True? Any thoughts on this whole
approach?
I have discarded one possible alternative approach, which
would be to listen at his usual level, then reduce the
level until he can just barely hear it and record how much
reduction that took. The problem with this dB-above-
threshold measurement is once again that if there is PTS
his higher threshold would make his music measure softer.
Any other ideas?
Thanks, and best regards,
Bob Masta
D A Q A R T A
Data AcQuisition And Real-Time Analysis
www.daqarta.com
Scope, Spectrum, Spectrogram, Signal Generator
Science with your sound card!