Inductor Orientation for minimised crosstalk

[Charles Jenkinson]

I have sourced all the crossover components from speaker hardware, but not the copper-surface laminated mounting board. I was thinking of getting the proper board but in reading about crosstalk I noticed that the particular subject and effect of '90 degree inductor orientation BUT with an OFFSET from the plane of one to the axis of the other' is not easy to find in the literature. All the info I could find shows crosstalk results for the plane of the inductor at 90 degrees aiming directly at the axis of the one perpendicular to it. I drew up the following diagram to illustrate the offset situation. It illustrates the layout of the components as shown on the speakerhardware version of the crossover I need to make .(http://www.speakerhardware.com/prebuilt ... -piezo.php)

How sensitive is crosstalk to dimension B? ...I appreciate it's all relative to the dimension A.

Of course I could still use the proper copper-surface mounting board, and mount the big inductor at 90 degrees - there's enough room, ...but I've also read that it's beneficial to eliminate unrequired extra connections (here: http://www.parts-express.com/resources/ ... ssover.cfm)

[Bill Fitzmaurice]

Put the high pass and low pass filters on separate boards and you won't have to worry about it.

[Grant Bunter]

Hi Charles,

Bill is very consistent in his statement, he always says it.
One reason in particular is it is much easier to see component layout should a crossover problem occur.

I found assembling two smaller boards easier to contend with.
You can see in both of my DR and WH8 build threads separate board and placement pics.
It should work well for your build as well...

[Michael Ewald Hansen]

+1 Its much easier to get the crossovers right if you put them on separate boards

[Charles Jenkinson]

OK, thanks Gents. The 'separate boards' is no problem - I had noted the consistency of the separate boards recommendation and the fact that IITP. There seems to be loads of room in the back of a jack, so it kind of throws one into a quandary on placement - if there was less room, it might be a no brainer. Wires running here and there need to be tied/glued down under the insulation, for longevity, I'm guessing.

Grant, or anyone, on the bit about wiring through the piezo's with one piece of wire; I have wire strippers that make the measured cut into the insulation, but, is the 'lever action' part doing something magic to remove the short piece of insulation once cut? I would (in my mind) have need to resort to a stanley knife, and slide it down the short-cut-insulation-piece to splay it off the wire...

Best regards,

Charles

[Grant Bunter]

Hi Charles,

I just hit the same spot in the wire with the lever action strippers about 3 times in rapid succession.
This opens up a gap (of, say 10mm) in the wire covering . Quickly folded the now exposed wire over the piezo tab and solder.
If you don't work quick enough, I found the wire covering tends to want to shrink back to it's original position.

Hope this helps...