x-over for Kef iQ30

[tuantran]

It is third order for the tweeter(two capacitors and one inductor 0.1mH).Sorry for the mistake.

[RAART]

Originally Posted by tuantran

I look at the pictures of the crossover and guess that the crossover is second order for the tweeter(two capacitor and one inductor 0.1mH) and first order for the woofer(1mH inductor) with woofer impedance equalization(one resistor and one capacitor).The crossover is bi-wired crossover.
No sound from tweeter?
No sound from woofer?
No sound on both tweeter and woofer?
Replacing those inductors will change the sound of the speaker(It may sound not good even there are high end components for the crossover).

I have no sound from woofer. I tested the speaker without x-over and woofer is working.

and yes this speaker can be bi-wired.

[RAART]

Here are some more pictures that you can take a look into...

[tuantran]

With two above pictures, I am able to draw the crossover schematic.Like I guess, the crossover has third order for tweeter and first order for woofer with impedance equalization for woofer.
No sound from woofer.
1- Resolder two places of 1mH inductor to check solder joints.
2- By pass 1mH inductor by a bus wire to check inductor.
3- Check red wire connection from crossover to woofer.
4- Check red wire connection from post to crossover.

[RAART]

I checked with multimeter all wires and they are fine, as well as inductor (I assume that it is only wound wire there) and they should be fine. I guess then it is one of the capacitors...

[RAART]

I think I found the problem... Need to check again however if you take a look at picture (bottom part of PCB) there is a hairline like cut. I assume that it was done by installation of the speaker in their factory but when I went and check the connection between the red wire and 6.8ohm resistor there was none. After I look closely this hairline was a crack on the PCB. I will solder a bridge there and recheck everything...

But now that I took out the x-over I think I will change capacitors and resistors as you suggested to get better sounding speaker! ;-)

In terms of modding the x-over, please let me know what can be done better?

[system7]

tuantran has done some good work for you there, my friend. You should be grateful.

This is all a bit odd. To lose bass entirely is not going to be the bass capacitor or resistor. It's going to be a fault in the bass inductor path. It's not really very likely the bass coil has got a broken wire, so you're really looking for a dry joint on the circuit board bass section or complete break in the speaker wiring I think.

Edit. Ah you've found the break then. Just reflow it with solder having scratched off some insulation, I'd reckon.

[RAART]

Originally Posted by system7

tuantran has done some good work for you there, my friend. You should be grateful.

This is all a bit odd. To lose bass entirely is not going to be the bass capacitor or resistor. It's going to be a fault in the bass inductor path. It's not really very likely the bass coil has got a broken wire, so you're really looking for a dry joint on the circuit board bass section or complete break in the speaker wiring I think.

Edit. Ah you've found the break then. Just reflow it with solder having scratched off some insulation, I'd reckon.

Of course I am grateful!!! I don't know why I didn't check prior that connection (I mean where the crack is)...

Thank you Tuan Tran!

But while I was reading that so much more can be done with this speaker in terms of the x-over I think I will do it while I got x-over already out... Suggestions?

[RAART]

Soldered and confirmed that it's working!

[Tomom]

Hmm...yes, don't waste money on "high end" component. If you can simulate crossover, that is the way to tell if something can or has to be changed...