Super thin/flat mains (& speaker) cable?

[Tim+]

We have a new sideboard/dresser unit and my wife would like to put a mini hi-fi unit on the sideboard. To do so would mean drilling a hole in the back of the dresser unit to run cables through which I'm very loth to do.

As the sideboard and dresser are constructed as two separate units there's a very narrow gap twixt the two that one could slide a playing card through. What I'm wondering is if there is any flat ribbon-like laminated cable that I could use to pass mains and speaker feeds through this gap. I've seen some speaker cable but nothing listed as suitable for mains.

Is this a no-no or doable? The "hi-fi" unit is double insulated and is only rated at 25W consumption so it's not got to carry much power.

Tim

[John Williamson]

For the speakers, you can use ribbon cable, but it'd be a definite no-no for the mains power, for which you need the correctly rated cable.

Depending on the internal supply voltages in the hi-fi unit, you may be able to convert it to run off a wall wart, with a low voltage power feed using the same ribbon cable as you do for the speakers.

[Lee]

Finding out if it will run off a wallwart and then run the low voltage DC through some thin cable is probably the practical answer

Maybe there is a (albeit limited) market for wireless power transfer in cases like this? More trouble (and cost) than it's worth but at only 25W you could have a couple of coils either side of the back of the dresser...

[Dave Plowman (News)]

I'd say the physical protection needed for a mains cable - two layers of usually PVC - would make it impossible. I've never seen speaker cable as thin as a playing card either. The sort of ribbon used inside PCs etc could probably be used for low power speakers if you paralleled cores.

Drill those holes in the back - you know it makes sense. ;-) Or even make a feature of what you've done by fitting suitable sockets/plugs to the back of the unit - that would make it easy to replace the 'mini Hi-Fi' when it fails. ;-)

[Lee]

Was meant to be tongue-in-cheek as it seems to be the latest fad, but it turns out there are some proof-of-concept 25W transfer systems available @ around 80% efficiency so maybe they will become more commonplace if the cost comes down.

[Mike Barnes]

Could you put a 6(ish)mm-high strip of hardwood or whatever between the sideboard and the dresser - all the way along - leaving a minimal gap where the wires are to go? As long as that arrangement was structurally sound it could be made to look quite decent. You could try it without risking anything and see how you like it.

[jkn]

You can certainly get (or make ;-) speaker cable as thin as a playing card ... I have some myself. It's made from thin silver ribbon (99.999% pure etc.) conductors, laid side-by-side onto transparent adhesive tape.

Google 'Allen Wright' and 'vacuumstate' for more info. Yes, I realise I'm opening myself up to the Ross Andrews baiters here - I regard myself as one of those baiters actually.

However I don't really expect the OP to go to these lengths, and I agree with others that you don't want to do this with mains power.

J^n

[Dave Plowman (News)]

Yup - drop shadows are all the rage these days. ;-)

[meow2222]

If you still need thin wire, enamelled copper wire is good for speakers. Mains, as said, isn't doable safely in card-thin format.

NT

[Tim+]

Hmm, interesting. That could work but I'm not sure it would meet with approval from my better half. Thanks for the suggestion though.

Tim

[Tim+]

Okay. I've been having a closer look at the construction of the back of the dresser and it's made with tongue & groove boards and if I could get skinny enough mains flex I could run it up the groove to a point where I could drill it invisibly. (From behind to a point behind a shelf edge).

Given the low power consumption, what's the skinniest cable that would do the job (and is available)?

Tim

[John Williamson]

The smallest normally available is rated at 3 amps, is 0.5mm2 conductors, and is about 5.4 x 3.4mm overall size.

The same area of conductor is available without the outer sleeve for your speaker connections, and is about 2/3 of the size.

[Tim+]

Yep, that's what's fitted. I'm after something "not normally available". Bell wire? ;-)

Tim

[Dave Plowman (News)]

Two or three core? Two is available in oval which might suit better.

I've got a newish mains lead here which came with an appliance - moulded

13 amp one end and figure of 8 connector at the other, so two core. I assume it conforms to regs. Cable measures 5.5 x 3.3 mm

[Brian Gaff]

No it would probably be very unstable and cause feedback. I tried this many years ago with some Sinclair amp modules. High current low voltage loses regulation by the time it gets to the amps. You need the psu right on top of the power amps.

I fancy this is not going to get put where it is needed. Maybe some kind of plug of wood can be f cut that can be reglued back later almost invisibly. Brian

[dennis]

You can do mains safely..

just step the voltage down run it through foil stuck to the units step it back up.

Easier to fit feet to the units and run normal cable underneath.

[sm_jamieson]

Put a recessed strip of wood under the dresser so the gap between it and the sideboard is enough for the cables. Paint it dark so it creates a shadow gap and it will probably look OK. Simon.

[meow2222]

You'd have a hell of a regulation problem, I don't know how you propose to address that.

One might see 15% regulation or thereabouts at that size, so 2 transformers would deregulate the supply by around 30%, plus there's already 15% regulation in the unit's built in transformer.

Better I think to go to dc, pass that thru the cabinet and to the 2ndary side of the moderate-fi.

NT

[John Williamson]

Nope, it *must* have two layers of insulation of sufficient thickness, and even for an installation such as you suggest, and a minimum physical strength to cope with the inevitable "I'll just pull this out to clean behind it" incident.

[Tim+]

Really?

Tim