posted
impedance: A measure of the complex resistive and reactive attributes of a component in an alternating-current (AC) circuit. Impedance is what restricts current flow in an AC electrical circuit; impedance is not relevant to DC circuits. In DC circuits, resistors limit current flow (because of their resistance). In AC circuits, inductors and capacitors similarly limit the AC current flow, but this is now because of their inductive or capacitive reactance. Impedance is like resistance but it is more. Impedance is the sum of a circuit, or device's resistance AND reactance. Reactance is measured in ohms (like resistance and impedance) but is frequency-dependant. Think of impedance as the complete or total current limiting ohms of the circuit -- the whole banana. Since AC circuits involve phase shift -- i.e., the voltage and current are rarely in phase due to the storage effects (think "time;" it takes time to charge and discharge) of capacitors and inductors, the reactance is termed "complex," that is there is a "real" part (resistive) and an "imaginary" part (bad terminology, but it means the phase shifting resistance part). To summarize: resistance has no phase shift; reactance (capacitors & inductors in AC circuits) includes phase shift; and impedance, is the sum of resistance and reactance. Just that simple.
Anyone else???
------------------ Sometimes the majority only means that all the fools are on the same side.
Use your ears to judge components, NOT your wallet! K.I.S.S.
Every thing affects the impedance of the speaker at any given time, amp circuitry, speaker box, voice coil temp, frequency, you name it, it affects impedance.
------------------ Sometimes the majority only means that all the fools are on the same side.
Use your ears to judge components, NOT your wallet! K.I.S.S.
The voice coil of the speaker has a definite resistance to DC current, measured in ohms.
When you move a speaker cone, the coil moves over the magnet to create voltage. When this voltage is created while there is a voltage already in the coil, it represents some resistance to the signal voltage.. That is reactance.
ShadowStar
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HEY! I'm looking for a CHEAP used Clarion Thunderdome.. Hook me up!
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