Crossover points and Ohm ratings

[Dr. Dan 10+ year member]

I was looking at the pre-built Dayton crossovers which state that they can work with both 4 and 8 ohm drivers:

http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=260-140&ctab=12#Tabs

The description says that the crossover point listed is when your using an 8 ohm load.

What's the formula for finding out the crossover point when using 4 ohm drivers?

Thanks!

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[JAZN 5,000+ posts]

I believe it's doubled.

http://www.bcae1.com/passxovr.htm

 

[alphakenny1 10+ year member]

i believe there is no formula in finding crossover pts and slopes. what might be important is to look at the frequency response graphs and maybe you can get an idea on where to choose the crossover pts and slopes if you are running active. in an active setup, its basically up to the user to choose the pts and slopes.

but generally if you double the ohm load that will double the crossover frequency i believe.

 

[thch 10+ year member]

i believe there is no formula in finding crossover pts and slopes. what might be important is to look at the frequency response graphs and maybe you can get an idea on where to choose the crossover pts and slopes if you are running active. in an active setup, its basically up to the user to choose the pts and slopes.
but generally if you double the ohm load that will double the crossover frequency i believe.

there definately are equations to define a solution to a goal.

the hard part is defining the goal such that a solution exists and is feasible.

 

[Dr. Dan 10+ year member]

My goal is to find, or if I have to, make, a low pass passive crossover with a crossover point of around 2khz.

This would be used for diy rear fill 4 ohm drivers being powered off a head unit without a built in crossover.

I do allready have some OZ Audio crossovers meant for their 6.5" components, but I belive the point on those is around 3.4khz, a bit too high for my taste.

I just want to keep those directional highs out of the rears, and I don't want to add another amp or processor to do it. Head unit power will be fine, and this whole setup would be cheap and easy...like me.

 

[jaygeorge1979 10+ year member]

why not just have some fun and make it yourself? parts arent too expensive, and this calculator is relatively easy to use:

http://ccs.exl.info/calc_cr.html

EDIT: this link has links to first order, second order, etc crossover calculators...you just need to figure out how steep you want your slope