crossing cable

[bananaspark]

I'm in the middle of a home automation layout (speakers in every room) and have already done one room with six lines of speaker wire (standard unshielded) going into various corners under a floating floor.

But i've got to spur out a few mains outlets and the mains cable will run directly across the speaker cables, -am a bit worried about the 50hz attenuation and possible clicks etc when high current appliances are switched on.

Would screened mains cable help (2.5mm 2 core and earth wrapped in foil) or place a short length of steel pipe a crossover points or should I get screened speaker wire?

thanks
b.

 

[Chri5]

The standard for separation between comms cables (voice, data and lets assume speakers) is 50mm of separation or a physical barrier such as conduit, trunking or ego tube.

Any cross over should be at 90 degs to the 240v cable.

Buy some flexible conduit, the plastic type and where cross overs are use 6" pieces to shroud the speaker cable. Plastic flexible conduit can be split with a stanley knife, so you can retro fit to cables already installed.

Hopefully on parallel runs you can maintain the 50mm gap via clipping the cables to keep the gap.

 

[electronicsuk]

I take it when you say cross-over you mean at 90 degree angles? If that's the case then don't worry at all.

Even if you were to run mains cable parallel to speaker cables over distance you shouldn't have too much of a problem. Noise is normally induced into audio systems at line level before the amplifier, as this is the point where the signal level is weak, input impedance is high and any small currents induced in the cable become far more apparent after they are amplified.

As we're talking speaker cables here, you've already passed the amplifier and it would take some quite severe induced currents to give anything you can hear on the speakers given the low impedance of the load you're driving.

 

[bananaspark]

thanks, I guess I'm flouting the Building standards rules but OK with Faraday.
will do without the added expense of screened speaker wire...