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<blockquote data-quote="thylantyr" data-source="post: 1249820" data-attributes="member: 560358">Dictionary; Impedance: something that impedes : HINDRANCE: as a : the apparent opposition in an electrical circuit to the flow of an alternating current that is analogous to the actual electrical resistance to a direct current and that is the ratio of effective electromotive force to the effective currentThe speaker has a DC coil resistance as can be measured with a meter. ie, a8 Ohm impedance drivers may have a 5.6 Ohm DC coil resistance. But whenyou send different frequencies to the driver the impedance of the driver changes,that&#039;s what the impedance chart tells you, at &#039;x&#039; frequency impedance is &#039;y&#039;.So.. the 8 Ohm nominal impedance is really variable and this changing impedanceaffects how the crossover works because the crossover is designed for a certainfixed impedance and when impedance is all over the map depending on whatfrequency is playing by the driver, then the crossover will perform differently.The zobel is suppose to stabilize the impedance so the crossover &#039;see&#039;s amore stablized impedance.When you split the frequency range, high pass for tweeters, band pass for midrange, low pass for woofers, if each driver is 8 Ohm nominal, the amplifiereffectively &#039;sees&#039; 8 Ohm as the load.Also, amplifiers don&#039;t freak out as much driving low impedance tweeters vs.midranges and woofers.If you have a &#039;dumb&#039; amplifier you can drive a much lower load if the load istweeters. ie, if your amp is only 4 ohm stable, you can drive 1 ohm tweeter loadsusually, but don&#039;t expect to drive 1 ohm woofers and they will be a bigger burden.I drove a 1 ohm tweeter load on my Adcom home amp in bridged mode. It&#039;sonly stable in bridged mode at 8 Ohms, but I took it down to 1 Ohm.Right now, that same amp is driving 0.8 Ohms on the tweeter array per channel.Piece of cake.</blockquote>

[QUOTE="thylantyr, post: 1249820, member: 560358"] Dictionary; Impedance : something that impedes : HINDRANCE: as a : the apparent opposition in an electrical circuit to the flow of an alternating current that is analogous to the actual electrical resistance to a direct current and that is the ratio of effective electromotive force to the effective current The speaker has a DC coil resistance as can be measured with a meter. ie, a 8 Ohm impedance drivers may have a 5.6 Ohm DC coil resistance. But when you send different frequencies to the driver the impedance of the driver changes, that's what the impedance chart tells you, at 'x' frequency impedance is 'y'. So.. the 8 Ohm nominal impedance is really variable and this changing impedance affects how the crossover works because the crossover is designed for a certain fixed impedance and when impedance is all over the map depending on what frequency is playing by the driver, then the crossover will perform differently. The zobel is suppose to stabilize the impedance so the crossover 'see's a more stablized impedance. When you split the frequency range, high pass for tweeters, band pass for midrange, low pass for woofers, if each driver is 8 Ohm nominal, the amplifier effectively 'sees' 8 Ohm as the load. Also, amplifiers don't freak out as much driving low impedance tweeters vs. midranges and woofers. If you have a 'dumb' amplifier you can drive a much lower load if the load is tweeters. ie, if your amp is only 4 ohm stable, you can drive 1 ohm tweeter loads usually, but don't expect to drive 1 ohm woofers and they will be a bigger burden. I drove a 1 ohm tweeter load on my Adcom home amp in bridged mode. It's only stable in bridged mode at 8 Ohms, but I took it down to 1 Ohm. Right now, that same amp is driving 0.8 Ohms on the tweeter array per channel. Piece of cake. [/QUOTE]

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