Power and speaker cable ok in same trunking?

[Glyn1959]

Hi, I have a single run of 2.5mm cable in a summer house running inside the smallest surface mount trunking (20mm?). I want to run 2 x speaker cables for radio/CD player along the same route. Can they share the trunking without any issues regarding
a) Heat
b) Interference
Your views appreciated

 

[Taylortwocities]

Regs dictate a separation of 2inches between such circuits.

i would recommend that you do this, that's unless you enjoy having a 50HZ buzzing noise on your speakers all the time.

 

[ban-all-sheds]

No - you may not mix them - speaker cables are not insulated for 230V

 

[dhutch]

The pedant in my suggests that the OP did not state the grade of cable used for the speakers, and that you are unlikely to pick up enough 50hz hum at speaker level to hear it, although you might if if was signal size.

Separate would however still be advisable.

Daniel

 

[bernardgreen]

For safety ( voltage separation ) keeping them 50 mm or more apart is best.

As for hum pickup.. if the speaker cable is flat , non twisted pair cable then running it close to mains cables over a couple of metres or more does pick up significant "hum" energy.

With low impendance speakers ( 4 8 or 16 ohm ) the hum sound produced will be very low and probably be drowned out by all but the quietest music.

With higher impedance speakers the hum sound can become intrusive.

 

[Taylortwocities]

But surely you'll hear it even more if nothing is being played..

 

[ccam108]

Why not just use mains flex for the speakers? Some 0.75mm^2 flat 2-core would work unless you have a particularly long run.

 

[bernardgreen]

Flat mains cable will work for speakers but as it is un-twisted hum pick up will happen if it is close to mains cable.

If you are rolling in cash and like to spend foollishly then http://www.russandrews.com/category-Speaker-Cable-PSPEA.htm is the place to look.

For example http://www.russandrews.com/product-Crystal-24-Speaker-Cable-3400.htm

This is not an advert but a comment on the extremes that some people will go to have the best possible sound. Some people doubt the improvement ( if any ) is worth the expense.

 

[ccam108]

Flat mains cable will work for speakers but as it is un-twisted hum pick up will happen if it is close to mains cable.

If you are rolling in cash and like to spend foollishly then http://www.russandrews.com/category-Speaker-Cable-PSPEA.htm is the place to look.

For example http://www.russandrews.com/product-Crystal-24-Speaker-Cable-3400.htm

This is not an advert but a comment on the extremes that some people will go to have the best possible sound. Some people doubt the improvement ( if any ) is worth the expense.

From experience, hum or buzz is only really a problem with unshielded signal cables with a much lower signal level (<1V p-p), or where there is something to introduce noise into the mains, such as a poorly filtered dimmer.

Very few speaker cables are twisted as noise is really a non-issue.

 

[OwainDIYer]

twisted speaker cable
http://www.canford.co.uk/Products/34-270_CANFORD-GPS-0.75-CABLE-2-core

 

[JBR]

Not really on-topic, but I'd never pay through the nose for expensive speaker cable. It has been shown that there's nothing to gain from it.

On the other hand, bell wire is far too thin for speaker use.

Personally, I'd compromise and use inexpensive speaker wire or even mains cable. Even thicker mains cable isn't expensive.