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patric
July 15th 03, 08:52 AM
Would anyone have any insight into the following:

Assuming a logorithmic increase in volume, how would I determine the
proper decibel value for any point between two decibel values? example
- At 0 sec, the signal is attenuated to -145 db, then at 1 minute,
the dignal is 0 decibels (unity gain). What would the volume in
decibels be at 30sec? Does anyone know of a mathematical function that
solves for this? Any help would be appreciated.

Patrick

Eberhard Sengpiel
July 15th 03, 10:02 AM
Patrick > wrote:
> Would anyone have any insight into the following:
> Assuming a logorithmic increase in volume, how would I
> determine the proper decibel value for any point between
> two decibel values? example - At 0 sec, the signal is
> attenuated to -145 db, then at 1 minute, the dignal is 0
> decibels (unity gain). What would the volume in decibels
> be at 30sec? Does anyone know of a mathematical function
> that solves for this? Any help would be appreciated.


Hi Patrick,

that seems to be easy. Because the dB scale is logarithmic
the value at 30 sec is 72.5 dB.
In your example time is proportional to the dB.
An other thing is the psycho acoustical sensitivity of our
ear brain system. That does not follow the logarithmic
values or the linear dB scale.

Cheers

ebs
German forum of microphone recordings
and sound studio techniques
http://www.sengpielaudio.com