[lexmark]

I really need your help – this is driving me made:

I have:

A Samsung LCD TV with 2 scarts (1 x rbg)
A Klegg home 5.1 home cinema system (separate amp, subwoofer, speakers). – 1xoptical, 1xcoaxial
A Sony DVD player (1 scart RGB) and coaxial
Sky+ (PVR3)

The Sky+ box is connected to the amp via optical and the TV via Scart (RGB)
The DVD player connected to the amp via coaxial and the TV via Scart

The problem I have is a loud humming noise from the subwoofer whenever both the coaxial and the Scart are connected to the DVD player when the TV is on.

The amp is not on and neither is the DVD player, but the sub-woofer is

If I remove the coaxial cable from the DVD player (or amp) the hum stops, if I put it back in it starts again. If I remove the Scart from the DVD player (or TV) the humming stops, it starts again when I put it back in.

So in other words if both the Scart and coaxial are connected you can hear the loud hum – if just one cable is connected the huming stops - but this is obviously not what I want

Rather than waste your time I have tried lots of things to try and eliminate this rather than just post on the board and expect miracles, Below are my findings so far:

The cables are all good quality (fully screened, oxygen free, gold plated etc..)
The TV is not too near the sub-woofer so not feedback
The sub-woofer is in a cabinet – but the problem still occurs when removed
I have tried other DVD players and the same thing happens
I have tried other cables and the same thing happens
The internal speakers of the TV are switched off so again no feedback
I have tried different Scart sockets (putting the dvd player in the RGB ) the same thing happens
I have tried different plug sockets and the same thing happens

I am really at a lose here, why is it just the Scart or coaxial from the dvd player?

Can anybody help??????

[WGLOVER]

Originally Posted by lexmark

I really need your help – this is driving me made:

I have:

A Samsung LCD TV with 2 scarts (1 x rbg)
A Klegg home 5.1 home cinema system (separate amp, subwoofer, speakers). – 1xoptical, 1xcoaxial
A Sony DVD player (1 scart RGB) and coaxial
Sky+ (PVR3)

The Sky+ box is connected to the amp via optical and the TV via Scart (RGB)
The DVD player connected to the amp via coaxial and the TV via Scart

The problem I have is a loud humming noise from the subwoofer whenever both the coaxial and the Scart are connected to the DVD player when the TV is on.

The amp is not on and neither is the DVD player, but the sub-woofer is

If I remove the coaxial cable from the DVD player (or amp) the hum stops, if I put it back in it starts again. If I remove the Scart from the DVD player (or TV) the humming stops, it starts again when I put it back in.

So in other words if both the Scart and coaxial are connected you can hear the loud hum – if just one cable is connected the huming stops - but this is obviously not what I want

Rather than waste your time I have tried lots of things to try and eliminate this rather than just post on the board and expect miracles, Below are my findings so far:

The cables are all good quality (fully screened, oxygen free, gold plated etc..)
The TV is not too near the sub-woofer so not feedback
The sub-woofer is in a cabinet – but the problem still occurs when removed
I have tried other DVD players and the same thing happens
I have tried other cables and the same thing happens
The internal speakers of the TV are switched off so again no feedback
I have tried different Scart sockets (putting the dvd player in the RGB ) the same thing happens
I have tried different plug sockets and the same thing happens

I am really at a lose here, why is it just the Scart or coaxial from the dvd player?

Can anybody help??????

Could be an earth loop with the two connectors.
Remember such things in my nerdy hi-fi days. Needed one earth to be disconnected. How you do this with your set up I don't know.

Then again, I could be talking rubbish.

[spooney]

I have not read your thread in very full detail but there are two things that came into my mind:
- If you have an active subwoofer plug it into another electric circuit (extension cable to another room) although thinking about it with the UK sockets this will not make a difference as you have only one option to plug in.
- There are sub woofer cables e.g. from Audioquest who come with an extra ground wire. For testing you can simulate this by using a stripped wire and twist it around the coax sockets (if they are made of metal) and fix them to the electrical neutral part of a socket on both cases with some stick tape.

[lexmark]

Thanks for the quick reply. The subwoofer comes with its own cables that are connected to the amp. I will try your other suggestion, although I would have thought by using their cables with their amp I should not have this problem?

I am also at a lose why it is just the connections to the DVD player?

[spooney]

Originally Posted by WGLOVER

Could be an earth loop with the two connectors.
Remember such things in my nerdy hi-fi days. Needed one earth to be disconnected. How you do this with your set up I don't know.

Then again, I could be talking rubbish.

Actually this was my first thought regarding the electrical plugs but then I realised you can not plug in an electrical wire straight and 180° with a UK socket.

[spooney]

Originally Posted by lexmark

I am also at a lose why it is just the connections to the DVD player?

Me too .
Earth loops are very difficult to sort out. Sometimes it is the cable, sometimes the device, some times another device in conjuction with the suspected one.
I think at least we can sort out the power cord part?

Just another thought after reading your thread in detail:
There are two types of SCART cables full wired and partially wired (all pins connected). Do you happen to know, if you have a full wired SCART?

Secondly: Could your TV be the trouble maker?

[lexmark]

Good point, not sure if fully wired, is there a quick way of telling. (Do we know if the one that comes with the sky boxes are fully wired?)

I hope it is not the TV, it is less than a year old!!!!, infact thinking about it cannot be as before I got the home cinema system (and therefore no subwoofer), it was all working fine...!!!

[spooney]

I was more of thinking the TV as the source. Maybe there is a soldering bridge somehwere. I am not familiar with SKY (exceopt the name).

I do hope you will find a solution.