Power audio amp off lighting circuit via transformer?

[SteUK]

Hi chaps/chappettes,

Wonder if I could get a bit of knowledge about the best way to rig up an audio amp in my loft.

I want to drive a pair of speakers from a small audio amp (12v, 2amp : peak amp output is 2x20W), but only want the amp 'on' when the lights are on. Can I treat it the same as the low voltage lights I currently have lighting the room? i.e. hook up a transformer to the lighting circuit and power it off the transformers output?

Obviously safety comes first and I don't want to be doing something that is not 110% safe and correct.

Cheers for your advice!

Ste

 

[davelx]

A transformer will not work. I'm guessing it's a car audio amp? It will need a reasonably well regulated DC supply of suitable rating. Best consult the place you bought it from. I'll let others comment on connecting to the lighting circuit

It's impossible for something to be more than 100% safe or correct. It's pretty much impossible for anything to be 100% safe.

 

[ban-all-sheds]

Why not look on eBay for a small stereo system which is meant to be used in a house not a car?

 

[SteUK]

Cheers for the responses

The ones I have been looking at come with AC power adapters, but I am not sure I want to be fuse spuring a socket off the lighting circuit. I am pretty sure that is not good practice.

Why not just spur off the upstairs ring main? I want it to only be on when the lights are on...my limited knowledge tells me that cannot be achieved if hooked up to the sockets circuit.

 

[OwainDIYer]

Without some complicated switching you will not get the amp to operate when 'any' light is on, but only when a specific light is on i.e. wired in parallel to the switched live for that light.

13A sockets should not be wired off the lighting circuit so get a power supply that has a mains flex end and wire it to a 3A fused spur off the lighting circuit.

If it's a Lepai style digital amp 20+20 watt will usually require closer to a 12V 5A DC supply not a 12V 2A DC supply.

 

[SimonH2]

I can't see why a 13A socket can't be used - suitably labelled. Worst case is that someone plugs in a larger load and trips the circuit protection.

As an alternative, fit a 5A socket. Of course, no-one would think of making up a short lead with a 13A trailing socket and a 5A plug

 

[mikhailfaradayski]

Just curious, but is there a reason why the amp should only work with the light?
Is there no requirement for sound during the day?