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Eric M.
01-27-2015, 10:20 PM
It's been about 25 years since I built a crossover. Back then all I used was the advertised impedance of the driver and plugged that and my crossover frequencies into a formula. I've been doing some looking around and see that there is lots of talk about Thiele parameters, free air parameters, V(as), etc. Is there now a better method for building crossovers using these or are these parameters primarily for speaker enclosures?

-I'm planning on building 2nd order, 12 dB rolloff crossovers. What does everyone here use for designing crossovers?
-Is it best to measure the impedance of each driver using a digital meter (DC resistance?) and use that reading for designing the crossover or if the speaker is labeled an 8 ohm, use 8 ohms in the formula?
-Where does everyone get their capacitors, coils and resistors?
-Which are the better types to get? Coils - air core? Resistors - non-inductive Mills? Capacitors - Film or foil capacitors?

In another pair of speakers I'm building I have original LX5, N2400 and N7000 crossovers. Are these out of date as far as quality in concerned? Am I better off building new crossovers or should I be considering rebuilding these or just use them as they are?

Sorry for all the questions. The more I search, the more questions I come up with. I think I need a little guidance.


Thanks,
Eric M.

RedCoat23
01-28-2015, 01:38 PM
If you've not already seen this, here's a good introduction on the diyaudio forum site.

http://www.diyaudio.com/forums/multi-way/189847-introduction-designing-crossovers-without-measurement.html

Eric M.
01-28-2015, 01:47 PM
Thanks, I have not seen that site yet. I'll check out the thread. I came across a program from Parts Express that designs crossovers.

https://www.parts-express.com/x-over-3-pro-software-cd-rom--500-919

Anyone use this?

Eric M.



If you've not already seen this, here's a good introduction on the diyaudio forum site.

http://www.diyaudio.com/forums/multi-way/189847-introduction-designing-crossovers-without-measurement.html

Mannermusic
01-28-2015, 07:32 PM
Thanks, I have not seen that site yet. I'll check out the thread. I came across a program from Parts Express that designs crossovers.

https://www.parts-express.com/x-over-3-pro-software-cd-rom--500-919

Anyone use this?

Eric M.

Yes. Used it some years ago - a good basic package for beginners or pros. For cone drivers only (Small-Thiele based). It is an older software package from Harris Industries designed for WIN XP originally back in the 90s, I think. Lots of updates. It is kind of clunky to use (like much of the software of the day) but technically correct and has an excellent learners manual. Good data base of drivers. Has a pretty good graphics program - especially for its day. Good print-outs. It was about $100 as I recall. Takes patience to learn and assumes you have some basic electronics under your belt. Maybe it has been improved by this time? But definitely worth $100 - like a basic course in crossover design.

The "pro" package is LEAP - used by JBL, I think. A couple of the serious/professional guys here have it. Expensive, can do anything if you have the driver input data.

Eric M.
01-28-2015, 07:51 PM
That's good to know, I'm going to order it up. I'll let you know if it seems"Updated" from the 90s. Although, if it's the 90's, it's about my speed.

Thanks,
Eric M.



Yes. Used it some years ago - a good basic package for beginners or pros. For cone drivers only (Small Thiel based). It is an older software package from Harris Industries designed for WIN XP originally back in the 90s, I think. Lots of updates. It is kind of clunky to use (like much of the software of the day) but technically correct and has an excellent learners manual. Good data base of drivers. Has a pretty good graphics program - especially for its day. Good print-outs. It was about $100 as I recall. Takes patience to learn and assumes you have some basic electronics under your belt. Maybe it has been improved by this time? But definitely worth $100 - like a basic course in crossover design.

The "pro" package is LEAP - used by JBL, I think. A couple of the serious/professional guys here have it. Expensive, can do anything if you have the driver input data.