Need Replacement For This Transformer, Klipsch RPW-10

[pcharm129]

Hi all. I'm trying to repair the plate amplifier on a Klipsch rpw-10 sub. I took the speaker to a repair shop, which told me the transformer is bad. I get a power light but no output at all. I tried looking up the transformer via the label info but no luck. And Klipsch is no help. Can anyone give me a hand with identifying the type of this transformer and where i can buy a replacement? Thanx in advance for any help you guys can provide!

 

[Les Jones]

I think the fault is very unlikely to be the transformer. This is not a normal transformer that works at mains frequency. It is part of the switch mode power supply. It is far more common for the switching devices (Transistors or mosfets.) to fail. Switch mode power supplies are not easy to repair even when you understand how they work. It is quite common for a number of components to fail and unless you find them all and replace them all the new components will be destroyed.

Les.

 

[Nigel Goodwin]

Yes it's switch-mode, VERY, VERY unlikely to be the transformer, and if it is there will be plenty of other damage as well. The transformer itself will be a custom made one, you can't generally buy off the shelf switch-mode transformers as they are all different.

As Les said - very difficult things to repair, and not a job for a beginner.

 

[fourtytwo]

I am not sure but we seem to be missing part of this plate amp in your pictures because you have concentrated on the transformer, may we have the rest please ?
There is a faston on the top left of the pcb labelled spkr, is that where one of the speaker wires is connected and if so where is the other ?
Have you measured the driver coil resistance, is it still intact ?
Given your power led is on I think the repair shop are probably wrong.

 

[unclejed613]

and if so where is the other ?

a little bit lower and to the left oriented 90deg from the firtst one marked SPKR-
the only parts available are the woofer and the complete plate assembly

 

[fourtytwo]

Gotcha, so have you checked the driver with a resistance measurement ?
Depending upon your experience you might like to remove the pcb from the chassis, Identify the voltage rails from the psu on the right to the amp on the left and very carefully measure them, please remember in this state the area to the right and above the transformer will be at 350V high energy, enough to kill some so don't do it unless confident.
I see you have another thread concerning a faulty sub, are you repairing these things for other people ?

 

[unclejed613]

I get a power light but no output at all.

this tells me the power supply IS working since the power LED is part of the input/preamp PCB connected to the main board by a 5-pin cable. so it's either a problem with the preamp, amplifier, or the woofer.... one thing i remember about this model is that the fastons have a tendency to get loose, especially on the woofer end.

edit: one troubleshooting tip for the OP... put the whole thing back together making sure to check the connections at the woofer end of the wires, and then try this test 1)start thumping on the woofer cone dust cover with a finger and listen to the sound of the thumping.... 2)while continuing to thump on the woofer turn the power on 3) if the sound of the thumping changes and the woofer suddenly feels stiffer, the amp and the wiring to the woofer are all ok, and your problem is more likely in the input/preamp section.

 

[schmitt trigger]

Very clever advice, unclejed!
Using the power amp's damping factor to ensure it is working. At least the output stage should be working.

 

[pcharm129]

I am not sure but we seem to be missing part of this plate amp in your pictures because you have concentrated on the transformer, may we have the rest please ?
There is a faston on the top left of the pcb labelled spkr, is that where one of the speaker wires is connected and if so where is the other ?
Have you measured the driver coil resistance, is it still intact ?
Given your power led is on I think the repair shop are probably wrong.

That's actually where the board ends. I just cropped to the edge for file size purposes on another forum.

 

[pcharm129]

Gotcha, so have you checked the driver with a resistance measurement ?
Depending upon your experience you might like to remove the pcb from the chassis, Identify the voltage rails from the psu on the right to the amp on the left and very carefully measure them, please remember in this state the area to the right and above the transformer will be at 350V high energy, enough to kill some so don't do it unless confident.
I see you have another thread concerning a faulty sub, are you repairing these things for other people ?

No. I went on 12volt.com to get help. But according to what your saying was a mistake. Because i was told to remove the yellow tape from the transformer. And i didn't think anything of it because i was under the impression that it was bad. So i cut yellow tape on both sides ti post a pic, and ended up slicing the coils.... Again, i was under the impression that the transformer was bad. Now i have to replace it either way it goes...‍

 

[pcharm129]

Here...

 

[Nigel Goodwin]

No. I went on 12volt.com to get help. But according to what your saying was a mistake. Because i was told to remove the yellow tape from the transformer. And i didn't think anything of it because i was under the impression that it was bad. So i cut yellow tape on both sides ti post a pic, and ended up slicing the coils.... Again, i was under the impression that the transformer was bad. Now i have to replace it either way it goes...‍♂

It's probably unlikely you can source a transformer?, service parts probably consist of just the complete board.

 

[pcharm129]

It's probably unlikely you can source a transformer?, service parts probably consist of just the complete board.

I did get in contact with Klipsch about a year ago. They had no replacement board. Guess I'm screwed...‍

 

[Nigel Goodwin]

I did get in contact with Klipsch about a year ago. They had no replacement board. Guess I'm screwed...‍♂

To be fair, a replacement board would probably cost more than the unit is worth.

 

[rjenkinsgb]

[Ignore]

 

[pcharm129]

To be fair, a replacement board would probably cost more than the unit is worth.

Thank you very much anyways. I really appreciate the help. I'll try to figure something out unconventionally. I'm pretty good at that...

 

[unclejed613]

service parts probably consist of just the complete board.

the whole back plate assembly.... and the woofer... these are the only parts available from Kipsch

 

[pcharm129]

the whole back plate assembly.... and the woofer... these are the only parts available from Kipsch

Thank you.