I think a "ideal" noise, with a gauss distribution, would have to have
an infinite pp if it is long enough.
However, in technical systems one normally clips a something like
3 x standard_deviation without loosing much.
This would set the crest factor to 1/3.
Andre
On 04.07.2014 07:47, Donatas911 wrote:
> Thanks.
>
> I'm working with underwtare noise research. There are plenty of different
> metrics used to describe a noise levels so there is a need to convert
> between a rms and 0-P or P-P metrics.
>
> _____________________________
> Posted through www.DSPRelated.com
>
Reply by Donatas911●July 4, 20142014-07-04
Thanks.
I'm working with underwtare noise research. There are plenty of different
metrics used to describe a noise levels so there is a need to convert
between a rms and 0-P or P-P metrics.
_____________________________
Posted through www.DSPRelated.com
Reply by ●July 3, 20142014-07-03
On 03.07.14 02.13, Donatas911 wrote:
> How to convert a sound pressure level value in dB rms to the level in dB 0
> to Peak value (having a values reference 1 micro Pascal)? As I recognized
> the relation for amplitude rms x 0.707 is valid for voltage values but that
> is different.
You are looking for the crest factor. It depends on the waveform.
sqrt(.5) = 0.707 is the crest factor of sinus waveform. Other waveforms
have other crest factors. But you man convert it to dB as well as any
other amplitude factor. 0.707 = -3dB.
Marcel
Reply by Bob Masta●July 3, 20142014-07-03
On Wed, 02 Jul 2014 19:13:48 -0500, "Donatas911"
<100629@dsprelated> wrote:
>Good day for everyone,
>
>A question:
>
>How to convert a sound pressure level value in dB rms to the level in dB 0
>to Peak value (having a values reference 1 micro Pascal)? As I recognized
>the relation for amplitude rms x 0.707 is valid for voltage values but that
>is different.
I'd be curious where you are going with this.
It is not possible to convert between RMS and peak values in
the general case, only in the case where you know the
waveform shape.
If you know that you have a sinusoid (RMS = 0.707 peak) then
you can always convert dB back to volts, apply your factor,
then convert back to dB. When you do that, you'll notice
that it's the same as finding the "dB value" of the factor
alone and adding or subtracting it from the RMS dB.
Best regards,
Bob Masta
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Reply by Donatas911●July 2, 20142014-07-02
Good day for everyone,
A question:
How to convert a sound pressure level value in dB rms to the level in dB 0
to Peak value (having a values reference 1 micro Pascal)? As I recognized
the relation for amplitude rms x 0.707 is valid for voltage values but that
is different.
D.
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Posted through www.DSPRelated.com