View Full Version : passive crossover help

03-26-2010, 02:52 AM
Hi all,

I've been happily running a 3 way system for a while

JBL 2405
Tad 4002 (with Radian drivers, the originals were too expensive at the time)
Tad 1601b

Crossing over at 800hz and 8khz.

Ideally I'd like to run the 4002 a bit higher (say about 10-12khz) but the ashly wont let me.

Anyway, I like using kit valve amps, and these consumer amps along with a pro cross over is making too much noise.

It will be cheap, fun, and possibly a success I am thinking to knock up a simple 1st order passive crossover to try instead.

From what I understand its..

Inductor on the bass
Cap on the mid (with an L-pad to find the resistor size)
Cap on the Tweet (with an L-pad to find the resistor size)

I have a good friend who will solder it up for me (he doesn't know yet, but he will hahaha)..

but I can't ask him to put figures into a calculator to work out the cap and inductor sizes I need.

I'm ''struggling at the edge of my understanding'', not being an engineer/similar, and wondered if any kind sould could help me punch the numbers?

As I understand it , all you need is the impedence of the drive unit and the frequency you want to crossover at and these programs chuck the figure at you.

I'm going with a simple 1st order, nothing fancy, maybe I can get a bit more elaborate in time with another go if I need to..

Help definately appreciated :)

Thanks everyone..

(most especially on-going thanks to Widget, without whom I never would have even gotten this far)

03-26-2010, 03:41 AM

stephane RAME
03-27-2010, 12:30 AM
http://petoindominique.fr/php/05-table.php (French Language)



04-28-2010, 07:37 AM
may want to visit the DIYAudio site,, it will calculate out various crossovers if you have the speaker specs,,


the attached crossover is using an Altec horn, and JBL tweeter and woofer,,