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<blockquote data-quote="squeak9798" data-source="post: 1392257" data-attributes="member: 555320">Yes, and that measues the DC Resistance (DCR) of the coil, not the nominal impedance.Resistance is the opposition to the flow of direct current (DC), and this figure remains constant.&nbsp; This is what you are measuring with your DMM.&nbsp; The resistance of the coil (in a T/S parameter this is referred to as either Re or DCR).Impedance is the opposition to the flow of alternating current (AC)....alternating current of course is what music consists of.&nbsp; Impedance is not constant and will vary with different variables such as frequency.&nbsp; Ever look at an impedance graph for a speaker?&nbsp; Those show you what the impedance of the speaker is doing over the bandwidth of frequencies.&nbsp; And the speaker&#039;s nominal impedance (shown in T/S parameters as Z or Znom) is sort of like an average of what load the speaker will present to the amplifier over it&#039;s operating range.&nbsp; A speaker may have a rated impedance of 4ohms, but it may only actually present a 4ohm load to the amplifier at a few frequencies...the rest of the time the actual impedance is higher or lower because it varies with frequency.The DCR will almost always be lower than the nominal impedance the speaker is rated for.</blockquote>

[QUOTE="squeak9798, post: 1392257, member: 555320"] Yes, and that measues the DC Resistance (DCR) of the coil, not the nominal impedance. Resistance is the opposition to the flow of direct current (DC), and this figure remains constant. [I]This[/I] is what you are measuring with your DMM. The [I]resistance[/I] of the coil (in a T/S parameter this is referred to as either Re or DCR). Impedance is the opposition to the flow of alternating current (AC)....alternating current of course is what music consists of. Impedance is [B]not[/B] constant and will vary with different variables such as frequency. Ever look at an impedance graph for a speaker? Those show you what the impedance of the speaker is doing over the bandwidth of frequencies. And the speaker's nominal impedance (shown in T/S parameters as Z or Znom) is sort of like an average of what load the speaker will present to the amplifier over it's operating range. A speaker may have a rated impedance of 4ohms, but it may only actually present a 4ohm load to the amplifier at a few frequencies...the rest of the time the [I]actual[/I] impedance is higher or lower because it varies with frequency. The DCR will almost always be lower than the nominal impedance the speaker is rated for. [/QUOTE]

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