Quiet-List 1997

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Re: Dealing With Noisy Neighbors


> Believe it or not, but the A-weighted scale was intended as a
> temporary measure - but after everyone started using it iot has sort
> of stuck...

It was originally intended as a measure of "loudness" in the 40 dB range,
but it didn't work because natural sounds aren't pure tones (sinusoids),
and it was derived from experiments with pure tones. However, further
research showed that the A scale could be useful to assess hearing risk,
and, up to a certain degree, to assess nuissance. (Interestingly, it is
most often used in the 45 and up dB range)

But, in fact, the A scale doesn't take into account a lot of elements
which are important as to the annoying potential of noise.

> There is a better parameter available - known as "Loudness" - this is
> more complex as it takes better note of the frequency distribution of
> the noise. 

Loudness is not directly related to annoying potential. A leaking tap in
the night will certainly pass any test based on level, loudness,
noisiness (yes, there is a scale using the "noy" unit, but it isn't
successful as well) or whatever descriptor like those ones--but it is
still very annoying!

> Unfortunately, there aren't many cheap loudness meters around yet

...Because it wouldn't make sense such a descrptor. It has only an
academic value. Would it be an interesting measure, with digital signal
processing (DSP) it would today be very easy and cheap to implement it.

We should press for more research to find out what bothers people as
regards to noise, and then try to quantify (or qualify?) it.

Best regards,

Federico Miyara

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