goodtimes

C5 and the one next to it. They are the biggest caps aside from the main caps.

There are a bunch of electrolytic caps on the amp board that can go bad. There are two in particular (same value and next to each other) that are most likely the culprits. If you are handy you can replace them very inexpensively. I went ahead and replaced all of the caps on mine including the main caps and have not had a humm/buzz since. Let me know if you want to tackle it and I can walk you through it. Or you can send them to me and I will do it. It really is pretty easy. Cheers!

So, after some time sitting off to the side I got my KSP amps fixed. First, I took them to the repair guy here locally and he instantly said "I bet it is the filter caps", so he replaced them and it was all good for a couple days and then bam, it's back. I got to looking through the service manual. Low and behold under trouble shooting it said......."Excessive Hum-check all filter caps", so I changed all of the filter caps on the amp module (including the big 6800uf main caps, got them for just over $6.00 apiece shipped from NY) and the two other small caps that were not listed as "filter caps". The amps both have a very slight hum that you can hear if the house is extremely quiet, computer not running, fridge not running, etc. From my couch I can't hear the hum, but if I get down right next to the sub I can, that might be normal I don't know. Other than that, they are sounding very nice! I got all the caps for both amps for about $50.00. Changing the caps was a breeze and they sound all that much better because I DID IT! haha.

I love mine too, I was referring to EdmundGTP's comment on his original KSP amps. Good luck on your KSP's, sounds like you are kicking @$$ on them!!

If you want to get rid of them I would like to take a stab at repairing them my self. PM me or what have you if you are interested. By the way thanks for all the info about the KSP-400's and your project!

Thanks for the reply and addvice. I found a guy locally that said he can fix it if I got him a schematic, so I called up Klipsch and while I was still on the phone the guy emailed me a cut-away, schematic and instructions for dismatling the speakers. So I will be giving the repair guy a call and see how it goes. Cheers!

Hey! New to the community. I just picked up a pair of KSP 400's, low and behold and sub hum from the right speaker. The other is fine. I opened up the lower panel to tighten on of the binding posts and found a capacitor laying in bottom of the plastic box??? Upon further inspection I found that it was empty and the filling (foil and paper) was up in the place that the cap should be and the two leads from the cap were still attached to the board. How in the %@#$ did this happen???????????? Any how I made sure the two leads were not touching themselves or anything else, hooked up the speaker and it is working. from what I can tell, there is no difference between the two speakers sonically. Will any cap of the same value (100uf 25v ) work to replace it? It can't be good for it to be open like it is. As far as the amp hum goes, I found a pair of KSP 400's on craigslist and the seller said he just had his amps sent in to Klipsch to be serviced regarding the infamous "hum". I was thinking about doing the same. What are your thoughts on the outbaord amps compared to the originals? Is it worth spending the money to have the originals repaired or just cut to the chase and go for the outboard amps?