DirtyErnie Posted November 26, 2019 Share Posted November 26, 2019 Looking at a 3rd order crossover, there is a Series element, shunt element, and another series element. In the high-pass section, that's a series capacitor, a shunt inductor, and another series capacitor. As I under stand it, these three elements are each adding 6db to the slope of the crossover, and the shunt element should be between the two series elements. Typically, the series elements are of different values, moving their respective break-points to slightly different frequencies depending on they type of x-over you're after (L-W, Butterworth, whatever) This leaves the question: Does it matter which order the series elements (capacitors specifically) appear in the circuit? Are there specific engineering reasons for typically putting the smaller capacitor first and the larger one second? Could the order be reversed without significant change to the behavior of the circuit? Thanks! Quote Link to comment Share on other sites More sharing options...
glens Posted November 26, 2019 Share Posted November 26, 2019 Wikipedia M-derived an K-derived, maybe? Quote Link to comment Share on other sites More sharing options...
mboxler Posted November 26, 2019 Share Posted November 26, 2019 The order does matter. The total impedance of the circuit is calculated from the load back to the source (or right to left when looking at a crossover schematic). Think of it like this. 8 / (10 + 4) = .5714... If we swap the 8 and 4 we get 4 / (10 + 8 ) = .2222... This is an oversimplification, but hopefully you get the idea. 1 Quote Link to comment Share on other sites More sharing options...
pzannucci Posted November 28, 2019 Share Posted November 28, 2019 On 11/26/2019 at 1:35 PM, mboxler said: The order does matter. The total impedance of the circuit is calculated from the load back to the source (or right to left when looking at a crossover schematic). Think of it like this. 8 / (10 + 4) = .5714... If we swap the 8 and 4 we get 4 / (10 + 8 ) = .2222... This is an oversimplification, but hopefully you get the idea. Also think of the first cap in line as operating against the highest impedance because of the devices behind it nearer the driver. The driver as the lowest impedance. Higher impedance requires the smaller cap. Quote Link to comment Share on other sites More sharing options...
Deang Posted November 28, 2019 Share Posted November 28, 2019 From the diyaudio forum: "will cause a 10dB peak in the response and a dip in impedance." I wise crossover builder once told me: "Just follow the damned instructions Dean and quit asking so many questions." 1 Quote Link to comment Share on other sites More sharing options...
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