Crossover Design - It's Not That Bad, Ken

[JohnA]

After reading the other similar post, I think we missed the boat.

Ken is looking for introductory information and probably not

discouragement. So, I'll give my best "wife" explanation, not the

how to build a clock, engineer's version. Vance Dickason's book

was wonderful help to me. Parts of it can be a tough read, if

your math is weak, but you can blow off the math most of the time and

still get a wealth of learning.

Crossovers use inductors and capacitors to limit the frequency band

allowed to get to a driver. Ordinarily, crossovers are described

by their "order", or slope. In a perfect world, drivers would be

purely resistive and the crossover would have perfect components making

the equations perfect. To begin with, Ta-Dah!, we're there.

A first order crossover reduces frequencies at 6 dB/octave. A

second order is 12 dB/octave and a 3rd is 18, and so on. Rarely

is more than a 4th order used, though Al is doing some that must be

20th order, or so. Luckly, the order is also the same as the

component count if you are building crossovers named after Mr.

Butterworth, who developed the equations. Most other designs

follow the order/parts count pattern, too, though the slope could be

significantly different from 6 dB per order.

If you understand that the real world is not perfect and test your work

after the prototype is built, you can build simple, low order

crossovers that sound quite good, at home. Low order crossovers

leave lots of room for error and, to my ears, even sound better.

Engineers have learned lots of tricks to compensate for real world

conditions. One of the biggest is testing and listening and

tweaking their designs after they see how it did.

I'm not going to minimize the possible complications in a crossover

design. When you begin to allow for driver impedance, eq built

into the crossover, protecting drivers from power, and differing

efficiencies, it can get extrodinarily complex, just like everyone told

you.

My point is, it doesn't have to be excessively complex, it you keep your designs simple.

[Al Klappenberger]

John,

You are right, of course. My problem is that I am a very poor teacher! My wife teaches reading at a local middle school. As a "real" teacher she reminds me often that I am no good at it at all! I also agree that if you start small, you can't go wrong. A 1st order filter has such gradual slopes that you just can't get it wrong!

Al K

[chops]

Is that what most of the Heritage line networks are? (1st order)

I only ask because they look rather simple. At least the Type B networks in my CWs do anyway. []

[Deang]

Yes, first order -- did you get an email from me chops?

Al, I disagree -- I think you're an excellent teacher. However, you suck at marketing.

[NOSValves]

Al, I disagree -- I think you're an excellent teacher. However, you suck at marketing.

I'd have to disagree.. Al's been instructing you for what a couple years now and your still clueless[] Of course that's probably not the teachers fault, you can lead a horse....

[TubeGuy]

Sucks at marketing? Al, we need a cool logo. With ALK networks and Trachorns, I don't feel quite confortable putting just the Klipsch logo on my Trachorned top bins. We really need a cool logo for the the top grills to properly disclose that these sysytems are of hybrid manufacture.[]

Marketing? When I see a chevron, I don't think of Chevrolet, I think Klipsch. Now Al, that's marketing. Let's get some brand recognition going here.

And Al, the pix of the bewildered Eagle on your home page DOES NOT qualify as a logo![]