Re: [DUG]: db calculation

[Nello Sestini]

 

         (db/20)

P1 = P2  e        

 

i.e. P1 = P2*exp(db/20)

 

 

not sure if this is what you are after

(and hope i haven't made some stupid mistake)

 

 

 

-ns
http://www.roserox.co.th

 

 

----- Original Message -----

From: "Ross Levis" <[EMAIL PROTECTED]>

To: "Multiple recipients of list delphi" <[EMAIL PROTECTED]>

Sent: Thursday, March 06, 2003 09:57

Subject: [DUG]: db calculation

> Here's a maths question for you.  I've never been that good at maths,
> particularly logarithms
>
> Does anyone know the formula to alter an integer value by a particular
> db value.
>
> I'm working on an audio app and I need to alter the volume by a
> particular db setting.  The volume can be anywhere in the range 0
> (silent) to 65535 (maximum).
>
> I know that db = 20 log (P1/P2) though I've also seen the 20 at 10.  How
> do I get  P1 (or is it P2) to the left of the equation.
>
> Thanks,
> Ross Levis.
>
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