Posted by Wayne Parham on May 24, 2003 at 07:33:24

In Reply to: Re: Compression Drivers arrived !!! posted by Adrian Mack on May 24, 2003 at 06:56:34:

You will need to use the formulas for calculating impedance and power through a reactive circuit, which isn't quite the same as pure resistance. The formulas are in the "Pi Alignment Theory" document and in electronics textbooks.

Impedance is found using reactive impedance formulas:

For inductance, X_L = 2πFL
For capacitance. X_C = 1/2πFC

Where:

X_L is inductive reactance, in ohms
X_C is capacitive reactance, in ohms
F is frequency, in Hertz
L is inductance in Henries (so mH is H x 10 ^-3)
C is capacitance in Farads (so uF is F x 10 ^-6)

This will tell you the impedance of your coils and caps.

If you know the voltage across a component and its impedance, you can calculate the power dissipated by the device using the formula P=E²/Z. If you know the current flowing through a device, you can find power by using P=I²Z. So find the reactive impedance of the device in question at the desired frequency, and substitute that for "Z."

• Re: Formulas - Adrian Mack 05:37:44 05/25/03 (1)
  • Re: Formulas - Wayne Parham 12:35:09 05/25/03 (0)