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<blockquote data-quote="defiance" data-source="post: 301337" data-attributes="member: 549442">Couple of quick pieces of info:Everyone keeps saying how you must get an amp that can handle a reduced impedence - however, this is not true.&nbsp; A passive crossover network is (and this is of course, VERY simplified) simply a network of resistances that varies with frequency.&nbsp; For illustrtation, let&#039;s use a 4-way passive 24db/oct crossiver.&nbsp; Frequency points are 80, 800, and 8k.&nbsp; Just for simplicity.&nbsp; Now, these are connected to a sub, midbass, mid, and tweet - all 4 ohm.&nbsp; Now, the way this is going to work is, for example, if a 20hz wave is sent to the crossover, the resistance of the portion of the crossover supplying the sub will be very low - whereas both high-pass sections will be extremely high.&nbsp; The resulting paralleled ohm load (assuming the crossover network is built properly) will still be 4 ohms.&nbsp; The same holds similarly true across the frequency bands.Another misunderstood portion of passive crossovers is resultant power.&nbsp; Everyone thinks that if you provide 400 watts to a 4-way crossover, each section will get 100 watts.&nbsp; This, however, is incorrect.&nbsp; In fact, for the same reasons listed above, whichever frequency band is playing will be sending the entire 400 watts.&nbsp; Well, I say entire - there is some significant portion of loss as a result of crossover resistance - however, it will be close.&nbsp; In that regard, passive crossover networks are actually significantly more efficient than active, since to match 1 4-way passively crossed over amp, you&#039;d need 4 actives.Why does everyone not do this, then?Simple - everybody wants to boom - and that level of power to your average tweeter would release the majik smoke in no time! //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif</blockquote>

[QUOTE="defiance, post: 301337, member: 549442"] Couple of quick pieces of info: Everyone keeps saying how you must get an amp that can handle a reduced impedence - however, this is not true. A passive crossover network is (and this is of course, VERY simplified) simply a network of resistances that varies with frequency. For illustrtation, let's use a 4-way passive 24db/oct crossiver. Frequency points are 80, 800, and 8k. Just for simplicity. Now, these are connected to a sub, midbass, mid, and tweet - all 4 ohm. Now, the way this is going to work is, for example, if a 20hz wave is sent to the crossover, the resistance of the portion of the crossover supplying the sub will be very low - whereas both high-pass sections will be extremely high. The resulting paralleled ohm load (assuming the crossover network is built properly) will still be 4 ohms. The same holds similarly true across the frequency bands. Another misunderstood portion of passive crossovers is resultant power. Everyone thinks that if you provide 400 watts to a 4-way crossover, each section will get 100 watts. This, however, is incorrect. In fact, for the same reasons listed above, whichever frequency band is playing will be sending the entire 400 watts. Well, I say entire - there is some significant portion of loss as a result of crossover resistance - however, it will be close. In that regard, passive crossover networks are actually significantly more efficient than active, since to match 1 4-way passively crossed over amp, you'd need 4 actives. Why does everyone not do this, then? Simple - everybody wants to boom - and that level of power to your average tweeter would release the majik smoke in no time! [IMG]//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif[/IMG] [/QUOTE]

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