Crossover - 1st Order


Or so I believe it to be! Ive read a tonne of webpages regarding introductory electronics. It is so confusing (Ive never done any electronics before).

Im doing my first DIY speakers, and just want the most basic crossover needed to actually make the damn things work. With the driver and tweeter being close enough to 6ohm impedance, I calculate that I need 10uF cap for the tweeter to crossover around 2.5khz , and probably a 636uH inductor for the driver.

My tweeter will have to live for the meanwhile being a few db louder than the driver - I dont quite understand the placement of the resister to bring this down. I cant get my head around exactly what effect it would have on the capacitor.

So - phase not withstanding, the theory is that I go to the electronics store and find out how to get 636uH worth of inductance, and 10uF worth of capacitance - I take my positive wire coming in, split it and on one split, before the tweeter I wire the capacitor in... and on the other split, before the driver, I wire the inductor in. Is this correct?

If so, are there any considerations I will need to bare in mind for the maximum voltage or any other ratings that are applied to the capacitor or inductor? Perhaps recommendations on what type of capacitor/inductor is best suited to crossover?

The power rating of the tweeter is 40W, and the driver is 30W. If you can give any help in this area where I so poorly lack, I would be most greatful.

 
Hi,

Just beacuse the power ratings are different, doesn't mean that the volume of the two are going to be different. This requires listening / testing or looking a Audax's website (if you haven't already)...(Just in case you were assuming that ;))

As for the wiring, you are absolutly correct. Then wire the other side of the speaker back to the negative terminal. Make sure you get the polarity of all the drivers the same (Wire the cap or inducter to the larger tag on the speaker) other wise you could get the situation where your mid/bass drivers cancel each other out!

If you order audio grade components from an audio supplier then you'll get the correct types...To be honest, as long as your caps and inductor are rated for 16V and over that will work. You'd distort the speakers before that! ;)

Gaz
 

Thanks for your prompt reply!

The tweeter is louder as it has a higher sensitivity (90db if I recall the website) and the driver is only 88db (apparently) although WinISD claims it should be 86 or so in the cabinet volume I am working on.

Ill make sure to not glue the back on permanently - Ill bet Ill want to open the speakers once they are done, and try fiddle with the crossover when I know a bit more.