2 way crossover design help

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This is the crossover schematic
 

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Try to use 6 Ohm resistor first. You can change the resistor value by adding 1 Ohm resistor in series with 6 Ohm resistor each time and test it until you hear the balance between tweeter and woofer ( you need several 1 Ohm resistors). I guess that the resistor value may be one of these values 5.6, 6, 6.8, and 7.5.
Good luck and have fun!
 
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Try this crossover(my design) for your speakers if you like it.
Impedance equalization can be calculated here.
Impedance Equalization (L-Pad) Circuit Designer / Calculator
Resistor value for tweeter is from 2 Ohm to 7.5 Ohm

Hi,

That site is how to design x/o's if your an electrician and know sod all about acoustics.
It will work but not that well, too simple. There is far more to proper simple hifi x/o design.

rgds, sreten.
 
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Re is driver (woofer) DC resistance. It is the DC resistance of the woofer voice coil.
Le is driver (woofer) inductance. It is the inductance of the woofer voice coil(not the 1.2mH of woofer filter). If you have a LCR meter you can have these values of the woofer voice coil.
 
I didn't get much mileage out of tuantran's Zobel correction. Really didn't help a lot, and frequency response was very awkward. It's generally agreed the Vifa tweeter needs a shunt and series resistor to get well behaved because its not ferrofluid damped so has issues at Fs and has an awkwardly low DC resistance of 3 ohms.

The below circuit looks reasonable to me. 3.3uF/0.5mH is more forgiving than 4.7/0.4mH being lower Q, and the adjustment of level will be done with the resistors AFTER the tweeter filter. But again, the values aren't too critical, say 20% will do, and you should work with what you have available.

This still has little bafflestep, which IMO is a good thing. It will work OK close to a wall. You will then adjust it by ear, because this is all very rough and ready. It remains to be seen how well behaved the woofer is. It has a peak around 4kHz. With respect to Thomas Akerlund in post #6, his circuit is a bit peculiar, and I wouldn't waste time on it.
 

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Ut-O

The coil changed on the woofer; can I use the .56 air (14gauge) or use the much thiner 19 gauge, .8 (as shown)?

Both are air core - in pic.

Btw, from the other builds with the 6db crossover, we thought the woofer sounded the best with the coil in the .7 range.

(They have surprizing amount of bass).
 
The coil changed to 0.8mH based on the exact Le value of 0.8mH for the peerless bass which tuantran dug up from somewhere. That's what you use for the filter. It works best. Filters really design themselves based on the woofer characteristics.

I keep telling you not to worry about tolerances, just get it about right. You will tweak it later to correct minor faults. You might make the bass capacitor smaller, for instance, which sounds more musical. You must balance that against coloration at certain frequencies. It's the 2-5kHz area which is going to be most exacting. That's where the high metallic harmonics of guitar and vocal sibilance and high trumpet energy reside. A lot of people are very good at adjusting by ear. It can be done.
 
Okay, thank you again for the design. Don't have a large cap for woofer, will need to order.
I can add two together to get to up to 15uf (for now).

I have a friend with a 6th sense when it comes to speaker, he hears things (good or bad) in seconds; which can takes me days - weeks.

btw, he really liked the vifa tweeter (I took the Madisound HSD kit to his place) .

This is great - thanks again!
 
This is very exciting, Doug. We wait with baited breath for what is essentially complete guesswork.... :D

Oh, FWIW, the woofer capacitor damping resistor is quite fussy for phase and woofer rolloff so changing from 1.5 ohms to 2.2 will make quite a difference. But who knows? Might be good.
 
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