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Re: TTS as surrogate for noise exposure measurement

> Since this is just for "casual" purposes, not research, 
> etc, he'd probably be happy with some sort of rule-of-thumb 
> metric...
iPhone available from family/friends? The iPhone microphone has a reputation of being calibrated quite well. There are dozens of dB-meters of any kind in the App Store. In a German computer journal "Noise Immission Analyzer" (https://itunes.apple.com/de/app/noise-immission-analyzer/id518336921?mt=8) got quite nice comments recently.

Not research grade but should be god enough for rule-of-thumb metric.

Am 15.04.2013 um 15:02 schrieb Bob Masta <audio@xxxxxxxxxxx>:

> 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!