I need help with new crossover

Hi all. I built crossovers 3 years ago for my speakers out of stuff I had laying around. They work but I think they could be much better.

So I have Heil AMT 4 ohms for tweeters, JBL 2441 16 ohm compression driver on 300hz Edgarhorns, and Lambda TD15 8 OHM woofers. I built 1st order xovers. I cross over at 700hz to the horns and 4khz to the Heil.

So what type xover do you think would be the best xover???


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They are the X model and I just looked them up. They say they can be pushed to over 1khz cleanly.
Feel like trying something out? Got access to an active XO?
Take the Oris/JBL combo off. Set the Heil on the cabinet over the 15" and maybe a couple inches back of the baffle plane where you'd think the acoustic center of the 15" is.

Got some 1/8" masonite? Cut 7"x9" (4) pcs. Stand one on edge and using electrical tape, mount it on a Heil outside corner. Tape it there. Do that on each Heil outside corner (facing you) and taper them back from the front edge at the cabinet base side panel and about 2-1/8" back of the Heil face plane. If you like this you can make (4) more for the back side of the Heil and 1/8" panels will meet at a point at the cabinet base side panels.

Like this <[ heil]> basically a tapered baffle.

If you can set a XO around 1200hz with a LR4 response, try it with just the Lambda 15.

I've been working on a 2way with a similar sized base cab. The baffle works well, good image presentation and boosts the xo frequency a bit for the Heil. I elevated the Heil about 3/4" and made an 1/8" ramp coming out of the Heil mouth down to the cab front edge. This added another 1db at xo where it meets the 15" drivers' vertical response. The blend is real good.

Hope you can try it out.
Hi Puppet. I actually tried something similar when I first started building them. The problem was I don't like the sound of the Heil down that low. To my ear it lacked the timber of a human voice. That's why I'm using the Heil for everything above voice range.
Apparently the 2 inductors are combined for the woofer. Did you measure this combo?

I can't see the capacitors values, could you post them?

You are using a cement resistor and an L-pad for mid level, why both?

I see two cement resistors for tweeter level, but I can't see how they are hooked up. (1 in series with + and the other in series with -)?

Have you tried reversing the midrange drivers polarity with respect to the woofer?

Is the woofer cabinet 4inches off the floor to get the mid and tweet higher in the room? If so you could try enclosing the bottom for better bass coupling with the floor


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I don't like the sound of the Heil down that low. To my ear it lacked the timber of a human voice. That's why I'm using the Heil for everything above voice range.
Maybe you've identified its limits, though maybe the acoustic configuration is a factor, be it baffling or a mismatch in crossing.

I don't know, but I would want to identify the lowest I could take the tweeter. I would want to cross it as low as I reasonably could, even if this meant a greater than first order rolloff.
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To have that luxury.. Circumstances usually dictate how one should be crossed. The other has to come into line with that. If it doesn't work then something other than the crossover needs to change.

If you are winging it I wouldn't outlay too much on the parts until you find what works.
To really get a top quality crossover, you need to start with measuring your speakers to have an id where to start. Then you can wit those measurements simulate it in software and get an exact crossover matched to your speakers. Now you're guessing in the wild. And that measuring is way more important to get it right than the quality of your components. A well designed crossover based on measurements with cheap parts sounds better than a wild guess with high quality components.

If you don't know how to do that, find someone who does and has the right equipment. I can do that, but i probally live to far from you to come over. If you got the measurements, and don't know how to sim, i can do that for you.
That makes sense Waxx. I have a Umic and REW for sound measurements and Woofer Tester 3 for electrical measurements. Which one is needed for crossover design?

A little search on this site would tell you that.

Getting accurate FRD and ZMA measurements

And more is found when using google...

i also use an Umik and REW, and DATS V2 for the impendance measuring. then i created FRD and ZMA files to sim the crossover in XSim.
I have four 4x8 sheets of Owens Corning 703 2" thick that I can make into a four foot long tunnel to measure my drivers in. Is that overkill?

Also, I'm going to do some studying today as I don't really know what a FRD or ZMA file is or where to find them or how to make them.