Help on vifa crossovers.

[Spiro007]

i biult the following speakers.
Vifa P17WJ/D25AG35 MTM Tower
http://www.kaiaudio.com/diy2001/kaiopen.html

here is the link to the woofer crossover.
http://www.kaiaudio.com/images/v3/V3-net1.gif
and the tweeter crossover.
http://www.kaiaudio.com/images/v3/V3-net2.gif

I biult the crossovers almost exactly like the one in the article and it sounded lacking in the midrange. I thought it was because i had to buy larger inductors and unwind them to get the right inductance, then i assured my self that i could not have botched it up that bad so i ran a simulation on EWB

I simulated the crossovers in EWB and i was kicking my self for already buying the inductors. doh!

has anyone biult these speakers?
is there a missprint in the article?
what crossover should i use?
is there any software i can use to make/test crossovers?
help!!!!!!!!

[Zaph]

I embarked on a project a while back consisting of a Vifa P17WJ/D25 combo. I did tons of reasearch, I modeled a lot of people's crossovers, and found most to be terrible, and some to be OK. Then with the help of a couple other guys, I confirmed that both of these drivers have huge consistency problems. There are different versions, and one crossover that sounds good with one set of drivers may not sound good with another set. Email me if you want a copy of the web page. (I had to take it down because I ran out of web space) There's a little more info on my Archives page.

For a 4 ohm MTM, a 1.5mH coil seems like it might be a little too large. I'm a guy who uses a lot of baffle step compensation but even that seems like too much. That may be the only problem with the crossover though I didn't model it or anything. I did my own MTM version and the largest inductor was 1.1 Mh, and that was with nearly full baffle step compensation.

[Bill Fitzpatrick]

I have a real problem with the 2 ohm resistor in series with the woofers.

[audio-kraut]

Hey - used the same speakers,also mtm, but had the xover designed by solen - Sounded very good and measured with a little shelving down 1.5 db from 2kHz on (xover point for the tweeter)

No I run the same config. aktiv with a dcx 2496 - no comparison to any passiv xover.

[Spiro007]

thanks zaph.
Could you email me some info on your design of the vifa MTM crossover.
spiro007@hotmail.com
i couldnt email you through the forum.

[Zaph]

Originally posted by Spiro007
thanks zaph.
Could you email me some info on your design of the vifa MTM crossover.
spiro007@hotmail.com
i couldnt email you through the forum.

Here's the crossover. I intentionally designed in a minor dip at 4.5kHz so this design should work ok with a few different versions of the D25. It also helps smooth other the off axis response.

If you have further questions, my email is available at my web site. (and you have to figure out what it is.)

[pathetic]

Zaph, I'm currently building a floorstander MTM with the same drivers and tweeter. I found this page and your crossover is for 4ohms. Will I be able to use your design as my receiver is 8 ohms. Thanks.