Shielding Speaker Cables - ** HOW **

[smarkgee]

I have an issue with an amp tripping. Ichange the amp it still trips. I change the speakers, it still trips, i have run another set of speaker cables....you guessed it. It still trips. It trips with the amp not connected to ANY source.I've even run an extension lead to take power from a different circuit in the house (before you ask!) So logically I have not got any problem.... All I have not tried is shielding the speaker cable. The cables run fairly close to the main fuse box for the house and they also run fairly close to other cables, including power cables. So my question is: HOW CAN I SHIELD MY EXISTING CABLES? Is there some sort of copper shielding that Ican buy similar to that found inside coax cable?? And will any such shielding make any difference? many thanks

 

[cheeseboy]

shielding the speaker cables won't do anything. Sounds like you need to get your electrics looked at.

 

[BigH]

You can buy sheilded speaker cables but not sure that will solve your problem. I would get an electrian to check your wiring first.

 

[Petherick]

Have you checked for damage to the speaker cables that may be causing a short?

 

[cheeseboy]

Have you checked for damage to the speaker cables that may be causing a short?

he says he's already changed the speaker cables for testing though....

 

[Covenanter]

I have an issue with an amp tripping. Ichange the amp it still trips. I change the speakers, it still trips, i have run another set of speaker cables....you guessed it. It still trips. It trips with the amp not connected to ANY source.I've even run an extension lead to take power from a different circuit in the house (before you ask!) So logically I have not got any problem.... All I have not tried is shielding the speaker cable. The cables run fairly close to the main fuse box for the house and they also run fairly close to other cables, including power cables. So my question is: HOW CAN I SHIELD MY EXISTING CABLES? Is there some sort of copper shielding that Ican buy similar to that found inside coax cable?? And will any such shielding make any difference? many thanks

Do you seriously think that your speaker cables are picking up something from the mains that would be powerful enough to "trip" an amplifier? Whilst in theory something like that might be possible I cannot believe it would ever happen in practice. Much more likely is that there is some mismatch between amp and speakers or you have just wired them up incorrectly. What is the amp/speaker combination? How have you wired them?

Chris

 

[drummerman]

Shielding makes sense but is a little more complex than just using a shielded cable.

This makes some interesting reading; http://www.analog.com/static/imported-files/tutorials/MT-095.pdf.

I use chokes on most cables but it is only one form of noise supression.

regards

 

[steve_1979]

When you say that it "trips" are you referring to a trip switch inside the amplifier or a trip switch for your house mains?

Unless the cables are touching and shorting I don't think that they're going to the cause of your problem. My guess is that there might be something wrong with your amplifier. It's probably worth getting a professional to have a look at it.

 

[cheeseboy]

. My guess is that there might be something wrong with your amplifier. It's probably worth getting a professional to have a look at it.

but he says he's changed the amp and it still trips... Unless it's two faulty amps?

 

[Supreme]

make sure the speaker cables aren't touching the chassis of the amp or anything like that

 

[steve_1979]

but he says he's changed the amp and it still trips... Unless it's two faulty amps?

Ahh yes so he did. :doh:

Does any other equipment make the mains trip or is it just hifi amplifiers?

 

[chebby]

Just use the usual process of elimination logic to find the cause.

Try different mains sockets or even a different room. (Or a different house.)

Try it without speakers at all (headphones).

Try it with different mains leads.

If possible try different speakers. (Does a friend or relative have a pair to borrow? Any old working speakers in cupboards or attic?)

Check the entire length of all cables for any cuts or crushed areas where a short might have occurred.

Usual stuff. You'll get there.

It won't make any difference shielding the speaker cables. Your amp is simply protecting itself from something that is wrong like a persistent short or incorrect connection. It could be inside the speakers or the amp or external connections. Mains wiring is unlikely unless you know something has changed just before the fault started.

 

[smarkgee]

thanks guys, i've done pretty much all the usual testing things. it's something wierd and i THINK I am reasonably intelligent!! (maybe others say not)

i have had this problem for YEARS and have spent days trying to solve it.

i've had the arcam power amp serviced (anyway i've tried with a different amp and with that amp standalone) i have celeestionA speakers which are 8ohm...anyway i changed them for 4 ohm...no difference. as i say i replaced the cables and used a slightly different route.

this morning i turned on a remote (large) PC screen and the amp tripped internally (NOT MAINS FUSE THE AMP FUSE). so was that some sort of surge on the main elec??? or maybe it was a power/video signal going down the DVD-i cable - as that cable would be fairly close to the speaker cables

honestly, i'm about to kill myself over this. :help:

all help so far appreciated

 

[smarkgee]

its not a permanent problem. after a few minutes it might go away (soemtimes stays longer than that).

 

[Supreme]

Maybe you need to get a sparky around to check out the house electrics.

 

[BigH]

As I said before you need to get a sparky in, your wiring does not sound safe and could cause a fire.

 

[steve_1979]

Maybe you need to get a sparky around to check out the house electrics.

As I said before you need to get a sparky in, your wiring does not sound safe and could cause a fire.

+1

It sounds dodgy to me. You should get it checked out by a professional to be on the safe side.

 

[Inter_Voice]

Maybe you need to get a sparky around to check out the house electrics.

As I said before you need to get a sparky in, your wiring does not sound safe and could cause a fire.

+1

It sounds dodgy to me. You should get it checked out by a professional to be on the safe side.

+2.

It really sounds that the house wiring is at fault and, like others said, get a professional to have the entire house wiring route check up before it is too late to regret.

 

[smarkgee]

thaks foir the feedback

i've lived in the house for 10 years. about 2 years ago the wiring circuits were routinely inspected and i have a safety certificate.

The question is

CAN I SHIELD SPEAKER CABLES FROM ELECTRICAL INTERFERENCE and

WOULD THAT SHIELDING ACTUALLY DO ANYTHING BENEFICIAL.

 

[Al ears]

There should be absolutely no need to shield any cable if it has been proberly constructed.

No difference.

However,from reading this post, it does appear you have a much more serious problem to be addressed first.

 

[cheeseboy]

thaks foir the feedback

i've lived in the house for 10 years. about 2 years ago the wiring circuits were routinely inspected and i have a safety certificate.

The question is

CAN I SHIELD SPEAKER CABLES FROM ELECTRICAL INTERFERENCE and

WOULD SHIELDING ACTUALLY DO ANYTHING BENEFICIAL.

GET YOUR ELECTRICS CHECKED OUT AND STOP OBSESSING ABOUT YOUR SPEAKER WIRES!! :wall:

 

[steve_1979]

CAN I SHIELD SPEAKER CABLES FROM ELECTRICAL INTERFERENCE

Most radio frequency electromagnetic shields work by placing an a barrier of conductivce material between the object that you want to shield and the electromagnetic field that you're trying to shield it from.

It is possible to bodge an RF shield yourself but I'd advise against it. If you want to use screened cables you should buy some new cables that are properly screened such as these: http://www.superfi.co.uk/p-2665-chord-carnival-silver-screen-speaker-cable.aspx

WOULD THAT SHIELDING ACTUALLY DO ANYTHING BENEFICIAL.

A screened cable will reduce the amount of RF interference that the analogue signal picks up.

I doubt that a shielded cable would help your problem though. I don't know what's tripping your mains trip switch but it doesn't sound like something that would be caused by RF interference. It does sound like it could be potentially dangerous though and you should get a professional to check it out.

 

[Covenanter]

thaks foir the feedback

i've lived in the house for 10 years. about 2 years ago the wiring circuits were routinely inspected and i have a safety certificate.

The question is

CAN I SHIELD SPEAKER CABLES FROM ELECTRICAL INTERFERENCE and

WOULD THAT SHIELDING ACTUALLY DO ANYTHING BENEFICIAL.

Yes you could although it wouldn't be easy but I can't imagine it would do anything beneficial. As others have suggested it sounds like you have something much more serious going on that you need to have checked by a qualified electrician.

Chris

PS IMO your problems are much more likely to be being caused by a fault in your speaker wiring.

 

[Al ears]

Covenanter,

PS IMO your problems are much more likely to be being caused by a fault in your speaker wiring.

See his original post. He has already changed out speaker cables, so unless both cables have the same fault, it is not them that's the problem

 

[Covenanter]

Covenanter,

PS IMO your problems are much more likely to be being caused by a fault in your speaker wiring.

See his original post. He has already changed out speaker cables, so unless both cables have the same fault, it is not them that's the problem

It could be if he is wiring them incorrectly! Cross connecting or connecting in serial for example. We've seen a number of posts to this forum where people clearly don't know how to wire speakers correctly. You can change the wire as many times as you like it won't correct incorrect wiring.

Chris