My kef psw 2150 sub woofer is making a buzzing sound at the back down low on the box. it still produces bass, but the sound is distorted and I can hear the buzzing coming out of the speaker too.

Well if it buzzes only for a couple minutes after turn on then it could be when the woofer starts pumping it produces pressure in the cabinet which creates a bonding motion that then closes the cracks, kinda like glue. Like blowing a balloon up in a box. The balloon is the pressure, OR Yes it could be your woofer is going bad. All speakers have voice coils. Tiny wire wrapped around a thin layer of cardboard then attached to the cone. This cone could be getting loose. But when the woofer heats up after a couple minutes it probably bonds the tiny wires so then the vibration or buzzing disappears. Over time woofers can die especially if it produces a lot of distortion, In a speakers life distortion kills and it doesn't matter how much power it can handle or how much money you spent on it.
Not all sub-woofers are alike. Some can handle the really low lows, and some can not. Check your settings too. Over time the vibration of the woofer will start to undo the glue, nails, screws, and even burn through the tiny wires in the voice coil. Oh and make your china crawl across the table... Have you been watching a lot more action movies? Some of the older woofers can't handle the newer digital deep bass frequencies... You may have to reconfigure your setup.

The internet is awesome, I just followed John Bloomfield's advice above and my 10-year-old Kef 1000.2 sub-woofer is back in action!

Is it so even at lower volumes?

Are you sure it's the sub distorting and not the front or center speakers?

If you designate them incorrectly as Large (which tells the receiver they CAN effectively produce bass frequencies) they will probably distort in the presence of low frequencies.

See Page 17, 19

Register and download the manual for free at retrevo.com

http://www.retrevo.com/support/Sony-HT-6600DP-Home-Theater-Systems-manual/id/390ag319/t/2/

Ok so no guarantees this will work, but it did for me and I knows it's very late but hopefully it will help someone else with a similar problem.

I had the same problem and as clmrt5000 said a very long time ago there could be an issue with a ground loop, although this is likely to give a high pitched buzzing sound.

This can easily be fixed by adding a switch to disconnect the mains earth from the back plate, or you can just unscrew the earth and tape it up, this fixed my ground loop, (some models already have a ground lift switch)

As for the "boiling" sound I also got a saw tooth wave sound (like a strange squeak or beep that changed frequency) this is caused by faulty components, and thanks to Frank Johnson (http://lug.demon.co.uk/kefrepair/?p=60) who suggested that you can simply and easily replace 3 capacitors on the main amplifier board (c58 - 47uF 63v or 100v) + (c52 & c53 - 220uF 25v) but stand them away from the board on the length of the capacitor leads to prevent them from absorbing heat from surrounding hot components (with heat shrink tubing to prevent shorting)

Now my sub works as good as new, apparently these 3 capacitors can cause all kinds of problems it's a common fault, so if you are handy with a soldering iron, or know someone who is you could save yourself a lot of money by repairing you faulty KEF sub.

p.s. if you have ANY of the KEF PSW subwoofers they all have similar issues, you can find a guide to fixing them at the link above, Frank is a brilliant and very helpful man.

Your amplifier is bad. I sent mine to KEF in NY and they fixed it for $100 US.

Manual posted at the following link:
http://lug.demon.co.uk/kef/psw2150_user_manual.pdf

If your amp has a "sub out" jack, that's the best way to hook up this sub. You'll just need a single RCA (also called "phono") cable. Connect it to the Left input on the sub, which should also be marked as "mono"

If your amp just has speaker-level outputs, then connect the left and right main speakers from your amp to the sub's high-level inputs, and then run wires from the sub's high-level outputs to your speakers.

If you're running a surround-sound setup, use the front-left and front-right speakers for this hookup.


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yes. A good idea. Kill power to the sub, then unplug and remove everything from the sub. go ahead and plug it in again and check for buzzzz.
That is test one. if you have buzz still, its the sub assembly. bad luck, but not impossible. If the buzz is gone its one of the signals to the sub. They can produce a buzzz without any signal coming from your stereo equipment. Replace the feed line, enjoy! BTW...Kef sure does sound clean. good choice.

single cable from where?

send me a request to my email address [email protected] and I send you a fix, Axel