[chuck-users] dbtopow(), dbtorms(), powtodb(), powtorms() off by 100 db (Robert Poor)

[Perry R Cook]

Oh yea, that too :-)

Thanx Adam.

PRC


----- "Perry R Cook" <prc at cs.princeton.edu> wrote:

> dB just implies 20log_10.  A reference must be selected.
> 
> The most common are dBV (1 volt = 0dB), dBm (0dB = 1 milliwatt into
> 600 ohms), and dBSPL (watts relative to threshold of hearing at 0dB).
> 
> I suspect that the implementers of this were thinking about
> the approximate 96dB of 16 bit audio, and the +/-1.0 float
> recommended max range of STK.  Thus a range of 0.00001=0dB
> to 1.0=100dB resulted.  Easy to change to any reference by
> just subtracting/adding/multiplying/dividing by a constant.
> 
> PRC