Need Help to Understand This Very Strange Crossover!
This crossover is from an old set of custom Focal driver based speakers. I'm especially baffled on how the tweeter's network works. Is this an elliptical/Cauer filter? Any of you gurus know what frequency this might be crossing the tweeter at?
Thanks for all of the help and any insight/discussion on this beast is greatly appreciated. Never really seen anything like it...
This crossover is from an old set of custom Focal driver based speakers. I'm especially baffled on how the tweeter's network works. Is this an elliptical/Cauer filter? Any of you gurus know what frequency this might be crossing the tweeter at?
Thanks for all of the help and any insight/discussion on this beast is greatly appreciated. Never really seen anything like it...
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Tried asking in the loudspeaker forum, but maybe I'll have better luck here. This is from an old custom made Focal based speaker. I'm particularly interested in solving the tweeter's filter type and function. Is it some sort of Cauer filter?
Can any of you gurus approximate at what frequency the tweeter is crossed? Any insight/discussion will be greatly appreciated.
Can any of you gurus approximate at what frequency the tweeter is crossed? Any insight/discussion will be greatly appreciated.
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And at around 3k.
//Anders
Thanks! Is there a way to simulate this on Jeff Bagby's crossover program? Or anywhere else so I can see visually what's going on? Even if it's not on these specific drivers. I've been playing around with Spice LT, but it's difficult to see the whole picture.
Thanks so much again.
What are you expecting to see?!I've been playing around with Spice LT, but it's difficult to see the whole picture.
What are you expecting to see?!
Trying to learn as much as I can. Never really played around with Cauer filters before.
I'm assuming that this is a 2.5 way and both woofers use Cauer filters as well? I wonder why they need such a steep filter for the baffle woofer. Is there a way to figure out approximately at what frequency the woofer is cut?
Are you sure that the PCD supports Cauer filter type?
I'm not sure. I haven't been able to figure out how to model this filter in PCD. I was wondering maybe one of you experts knew some tricks.
Do you have FRD data for the Focal woofer?
Unfortunately I do not have any FRD or ZMA files for any of the Focal drivers.
But modeling these crossovers with any drivers would still be of value to me as it would give a general idea of what the crossovers are doing.
Here is the LF response with a generic 5R load, I think it is not a Cauer filter, since the passband has no ripple to speak of... but the stop band looks very messy, wonder what Focal was thinking.
View attachment 547033
Very interesting! Are you able to model the tweeter and the midrange/mid woofer? Tweeter is 7.4 Ohms, midrange/midwofer is 6.4 Ohms. Just for kicks...
A speaker is not a simple impedance it always have peak & dip and phase shift...
So simulating cross over with resistive load will never give the exact result
I this desing I think they also made some kind of equalisation to compensate drivers response .. or enclosure .... this make the circuit even more difficult to figure out ...
So simulating cross over with resistive load will never give the exact result
I this desing I think they also made some kind of equalisation to compensate drivers response .. or enclosure .... this make the circuit even more difficult to figure out ...
Completely demented design that I hope you are not plugging into your expensive amplifier, because it is an amp killer! 
The tweeter filter is some hopeless implementation of a KEF Acoustic Butterworth, with an Fs notch from the snubbing 0.33uF capacitor at 1.2kHz.
There are undamped notches all over the place. Without knowing what the drivers are, it is hard to say what this designer was thinking of. He needs help.
The tweeter filter is some hopeless implementation of a KEF Acoustic Butterworth, with an Fs notch from the snubbing 0.33uF capacitor at 1.2kHz.
There are undamped notches all over the place. Without knowing what the drivers are, it is hard to say what this designer was thinking of. He needs help.
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- Completely stumped on this filter type, need help.