Pio 812 and Kef SW interference/thumps


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May 14, 2003
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Hi all, checked a few threads but no solutions.
I'm running the KEF eggs off a Pio 812. Whenever I switch between sound options, between feeds, and even when I change DVD menus - I'm picking up horrendous thumps.

I've the sub connected via splitter and cable from SW out on the amp (this is a 9m cable (ixos) i just bought last week here) tried another cable but same problem - also tried without splitter - ditto). DVD is connected to amp via coax. Amp has earth on.

Xover at centre (i.e. 12 o'clock), Input just up (as I like the base subtle). Main thing causing concern is the dvd menu noises. Minority Report menu screen sounded like a drum & bass session.

One other thing...The SW isn't always recognising the signal. Yesterday while watching MTV via analogue it kept shutting itself off. This morning I switched it on, light stayed red, gave the cable a jog and it came on again.

So is it the SW? Or the amp? Or even the cable? Only had it a week and a half and the problem only became really noticable last night but as I said same issue with old cable.

Any ideas? Please help!!!!
This might be of help to someone else. Just spoke to Ben at KEF. It seems the 'muting transistor' in the amp has blown. This is generally caused by a surge if the cables are unplugged when the SW is on. So more annoying than anything and repairable - and it doesn't affect the speakers etc. Now I start the witchhunt to find out if anyone has been playing with the cable!

Only problem now is that I use squarts so now I have to send the amp back and dig out some old scarts to hear sound thru the TV again. Looks like the City Of God DTS will have to wait a bit.

You beauty. I've had this problem since I bought my Kef 2005 system back in April and despite talking to Kef and posting on here nobody could give me an answer to the problem.
Pleasure. If your amp is still under warranty it should be covered. If not I understand it's not a horrific expense. Ben also advised against leaving the amp on auto all the time - I think it was to do with sheer wear & tear. He keeps his on manual. Certainly cuts the risk of surges. Also gave great advise on why best not to use a splitter cable adaptor...I think it was it increases volume by 3db but cuts input by half...or something. I got a bit lost there. Cheers T
Using a Y lead will sometimes halve the input impedance of the sub. I guess it should go no lower than about 10K, so probs from this are less likely.

Make sure all speakers are set to small if you use Auto mode on subs as the sub will always get a signal.
A Y lead helps mostly with auto mode/standby on subs as the inputs to the sub are +3db summed.
This = double signal level.
gave the cable a jog and it came on again

Could it be a faulty cable that damaged your amp?
If the cable is shorting internally it could well damage an output stage in your receivers pre amp.

Can you unscrew your phono plug (is it metal)?

Just a thought!
Hi Wookie, TX for the above. I can unscrew it but couldn't see anything. Here is a question tho/

The s/w has the usual line in's. Does it matter which of the two you use to take the amp signal if you are only useing a single cable?
Use either line in L or R.
Just make sure you don't connect the sub woofer out on your amp to a low level high pass out (there are two on your sub).
Cheers. No. That one I double checked thank God. Tx for the help. Much appreciated. T

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