Cabling trunking isolation and separation - advice and ideas

I am re-jigging my “music room”.
I am planning to provide a dual (plastic) trunking at skirting level to route my cabling.
I was planning for the lower trunk to carry the mains cable to a bank of unswitched sockets for the equipment.
The upper trunk would carry the speaker cables, ethernet cable and a long RCA-cable (from the tv/AV).
I also thought of using small plumbing insulation tubes (used for lagging pipes) for some cables inside the top trunking. Whilst this will not provide isolation it may provide separation.

Which cables carry the most risk of cross-interference and need attention?

Any ideas or advice?

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The domestic/industrial regs have it all covered.
Power cables become a growing noise emitter as current flow (amps) increase.
The rest is length & individual cable screening.
Separation is not normally required in domestic installations as its most unlikely to have a run of of power cable carrying anything like as high as 32 amps & together with ethernet runs longer than 15m, however some separation can always be considered worthwhile & these are useful guidelines from the regs.
With no metal separation (conduit or trunking)
Unscreened power cable & unscreened ethernet - 200mm
Unscreened power cable & screened ethernet - 50mm
Screened power cable & unscreened ethernet - 20mm
Screened power cable & screened ethernet - 0mm


Many thanks - this gives me a good starting point.
(PS I did have to get my tape measure to convert them to “real” distances!)

As I am only looking at about 18 feet (sorry) for the mains and ethernet cable lengths the option to look at screened cables for both, as my trunking is plastic, is very feasible and a good starter.
This is an exercise in improvement of my system not just getting over the line.

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We’re in the middle of a new home build and I specified with the architects the following related to in-wall cables:

  • Trunking separate tubes for mains and other.
  • dedicated speaker cable trunking in living room.
  • 10cm separation between speaker cable trunking and anything else where possible.
  • Trunking access panels on each floor for replacement of data cables if needed.

You don’t to worry about what to use for the tubing. It’s all standard. Cable trunking for in-wall is generally like narrow vacuum hose colour coded depending on what you shove through it.

None of it was seen as a problem. If you are retrofitting trunking to the outside of skirting boards your options are simpler: paintable mole.

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In commercial buildings, large and small, the separation between power and analogue cables will be specified as 100mm.

As Feelin Zen has in his house. :+1:

Are the speaker cables OK running together?
What are they affected by?

Speaker cables are fine together but you should avoid running them parallel to mains without some distance (as has already been discussed).

Your biggest problem with speaker cables will always be arranging the slack in a way that minimizes noise. I used the Naim recommend zigzag method once. Awful. Picked up AM radio!

Made some good progress.
Used two plastic trunks (all from B&Q or similar) which I glued together and then screwed the top one to the wall (with the trunk covers facing inwards from the wall) (see Fig. 1).
Thought about triple trunks (see Fig.2) but this interfered with the mains sockets so had to revert to plan A.

The mains cable sits on the lower trunk and the ethernet sits on the second trunk. I overlaid both the mains and ethernet cables with silver metal conduit for shielding (see Fig. 3). At the joints I overlapped the metal conduit to maximise shielding.

The speaker cables are then run in the top trunk above the shielded ethernet cable using a plumbing insulation tube just to keep them tidy above the shielded ethernet cable.

I have cut half-moon slots in the edge of each front facia as necessary which avoids the need to thread plugs etc. through holes (see Fig.4 and 5).

All sounds fine and works well.
Thanks to all for your input and advice which I have tried to take on board especially about cable screening and separation.

Comments and criticism are welcome!

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See my update and thanks for your help.

See my update and thanks for your help.

See my update and thanks for your help.

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Similar to the way I did it, but I used three compartment trunking

Speaker cable in the big middle section, power cable in the bottom section and signal cable in the top section.

You can even zig-zag NAC A5 cable in the middle section.

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All finished and looking tidy.

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You can buy multi compartment trunking as part of a system including bends and cable outlet plates etc, they look much better and are available is different sizes. They also include the option of add on metal screening too. Lots about available from electrical wholesale outlets.

I wish I had known that when I started.
However I am very pleased with the outcome.

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