Kef Chorale III (3) woofer problems

[Tim897316]

I own 2 KEF chorale speakers. One of them works perfect. The other one's woofer doesnt seem to work. Each one has a 6 inch woofer and a 1 inche tweeter. The tweeter seems to work fine on the one with the woofer not working. I did an experiment seeing if it was the woofer or the wiring . The woofer seems to be fine but i was wondering what im gonna need to fix the speaker so the woofer works. Maybe a new fuse or something?

 

[Sheep]

There shouldn't be fuses in speakers. Judging by Kefs website, they look to be normal non powered speakers.

Have you taken them apart to see if the wires are still plugged in? Are they connected properly at the back?

SheepStar

 

[Seth=L]

There shouldn't be fuses in speakers. Judging by Kefs website, they look to be normal non powered speakers.

Have you taken them apart to see if the wires are still plugged in? Are they connected properly at the back?

SheepStar

Some older speakers have protection fuses for the tweeter.

 

[Sheep]

Some older speakers have protection fuses for the tweeter.

Great. It's a woofer problem.

SheepStar

 

[Seth=L]

Great. It's a woofer problem.

SheepStar

Right you are.

 

[Tim897316]

so.... what do i do? lol

 

[Seth=L]

so.... what do i do? lol

Maybe the cross-over is damaged, if the driver works. See if you can order another x-over from Kef.

 

[highfihoney]

Great. It's a woofer problem.

SheepStar

 

[TLS Guy]

I own 2 KEF chorale speakers. One of them works perfect. The other one's woofer doesnt seem to work. Each one has a 6 inch woofer and a 1 inche tweeter. The tweeter seems to work fine on the one with the woofer not working. I did an experiment seeing if it was the woofer or the wiring . The woofer seems to be fine but i was wondering what im gonna need to fix the speaker so the woofer works. Maybe a new fuse or something?

Sorry, I have only just seen your post, so my help is a few days late.

What Experiment did you do to show that the woofer works? Did you swap them between speakers?

There is no fuse in the chorale. The low pass filter is second order with a notch filter.

http://www.hifiloudspeakers.info/Anatomy/Crossovers/DN13SP1015Chorale/Gallery/pages/chorale.htm

If the woofer really does work, then there must be a bad solder joint, or the 1.1 mH inductor is open circuit. The latter unlikely. The most likely component to fail is the 16 mfd cap, however they don't usually fail by developing a short, but I have seen it. Since that is a possibility it is putting any amp connected to that speaker at risk.

This will be a very simple circuit to trouble shoot and repair, if the crossover is indeed at fault. If you want to do it yourself I will guide you through it. Do you have any test gear at all?

 

[Tim897316]

yeah id love for u to guie me through it. But i have no test gear. do u just need a voltometer? Im totally noob to all this **** but im DYING to learn it. teach me xD

 

[TLS Guy]

yeah id love for u to guie me through it. But i have no test gear. do u just need a voltometer? Im totally noob to all this **** but im DYING to learn it. teach me xD

The first thing to do is to disconnect the woofer. Then make see if there is continuity from the + speaker terminal to the + wire to the woofer. Do the same for the -. If there is no continuity use the ohm meter to see where the circuit is open.

If you put an ohm meter across the terminals of the woofer it should read 6 to 8 ohms. Then if you put a 1.5 volt cell across the terminals the cone should pop in and out as you make and break the circuit.

If the woofer fails either of these tests in needs re coning.

If the woofer is OK disconnect the 16 mfd cap and see if it has a short with your meter.

Now put you ohm meter across the the 1.1 mH choke. It should read around 0.3 ohm. If it will not conduct it is open circuit and needs replacing

If the the choke is OK, then reconnect the woofer without the 16 mfd cap in circuit. If you hear sound from the woofer, then the cap needs replacing.

See how you get on.
Merry Christmas.