Passive Crossover Design

Hi guys,

I have designed this passive crossover and wanted to know if it looks ok. I can get all the parts at reasonable prices just wanted someone with a more professional eye to look over it before I put an order in and start making it.

Any help would be appreciated

TIA

expectations are: 2nd order butterworth 2 way 200hz x/over with 6db ATT on the HF +/- 5%

C1&2=22uf

C1&2a=47uf

C1&2b=1uf

L1=9mH

L2=9mH

R1= 3.99r

R2=8.04r

Edited by DJ-Versatile - 24 November 2016 at 5:12pm

If you are the smartest person in the room, you're in the wrong room....

Thanks for the reply snowflake, this is my first attempt at a x/over so please excuse my ignorance I'll have a go at redesigning it tomorrow and adding a zobel filter :)

If you are the smartest person in the room, you're in the wrong room....

Here is the RCF MSW8 300w 150hz crossover to show how chunky thigs get, 12" driver & lighter for scale, rubbish pic but you can get an idea

As it is, you don't want to build that circuit. Like phil suggests if you want those capacitors to add up in value they need to be wired in parallel. This is because impedance is proportional to the inverse of capacitance and so the series/parallel resistor relationships reverse to the other way around too.

We also need to know the impedances of the driver and HF you plan to connect it to as well. R and L for the driver, and a nominal R for the tweeter will do.

Like Phil says also, consider a zobel for the woofer once you have measured its inductance to give it a resistive impedance outside of resonance and make it easier for an amplifier to drive it.

When you calculate resistors for an Lpad, you also should take into account the resistance of their loar (tweeter R) and size them accordingly so that the L-pad in combination with the tweeter still presents the same effective resistance to the filter before it. Or you will shift your expected crossover point.

Lastly I would highly suggest ditching fritzing. It is really only good for making nice graphics of circuits on breadboards. Sucks for anything else. Get LTSpice and don't look back. It will also simulate the result of your circuits so you can be absolutely confident in your circuit before you build it for real and buy expensive parts.

He certainly has designed it, whether it will work as intended is another question!

DJ-Versatile wrote:

odc04r wrote:

He certainly has designed it, whether it will work as intended is another question!

be nice guys it's my first attempt Embarrassed

Just playing Big smile

At least you're asking if it's right or not, and by the time we're finished it will be.