********************** Inches to Ohms **************************
Basic acoustics tells us that an open baffle acts as a high-pass
filter with a cutoff frequency ( Fc ) defined by the formula :
Fc = 4560 ( Hz ) / baffle-diameter ( inches )
Basic electronics defines the cutoff frequency of a R C
( resistor - capacitor ) high-pass filter with the formula :
Fc = 1 ( Hz ) / ( 2 pi * r ( Ohms ) * c ( Farads ) )
Therefore since Fc = Fc :
( 4560 / diameter ) = 1 / ( 6.28 * r * c )
Converting inches to Ohms :
( 4560 / r ) = ( 1 / ( 6.28 * r * c ) )
4560 = ( 1 / ( 6.28 * c ) )
( 1 / 4560 ) = 6.28 * c
c = 1 / ( 4560 * 6.28 ) = 1 / 28637 = 35 uF
Ergo :
To simulate an open baffle using electronics software we may
use a R C highpass filter where C = 35 uF and R = baffle diameter
( in inches )
Example : 8 inch bare driver
Basic acoustics tells us that an open baffle acts as a high-pass
filter with a cutoff frequency ( Fc ) defined by the formula :
Fc = 4560 ( Hz ) / baffle-diameter ( inches )
Basic electronics defines the cutoff frequency of a R C
( resistor - capacitor ) high-pass filter with the formula :
Fc = 1 ( Hz ) / ( 2 pi * r ( Ohms ) * c ( Farads ) )
Therefore since Fc = Fc :
( 4560 / diameter ) = 1 / ( 6.28 * r * c )
Converting inches to Ohms :
( 4560 / r ) = ( 1 / ( 6.28 * r * c ) )
4560 = ( 1 / ( 6.28 * c ) )
( 1 / 4560 ) = 6.28 * c
c = 1 / ( 4560 * 6.28 ) = 1 / 28637 = 35 uF
Ergo :
To simulate an open baffle using electronics software we may
use a R C highpass filter where C = 35 uF and R = baffle diameter
( in inches )
Example : 8 inch bare driver
