Amplifier 12v Source

[Eddie Twadds]

Some electrical input needed on the best way to power my amp for my ToM refurb.

Using the amp in the pic (250w per channel should be fine ) I want to tap a 12v, switched power source. Previously I've taken 12v and ground from the coin door interface board but it's very noisy, picking up all the hum and noise from the transformer and circuitry.

In theory, and subject to correct power rating, is there any reason I couldn't wire a transformer like this one https://www.ebay.co.uk/itm/AC100-24...r-Supply-Transformer-Adapter-UK-/172768516266 after the switched side of the power box (basically get rid of the plug and hardwire it), thus avoiding all the interference, and potential loading issues?

Opinions welcomed.

 

[Paul]

Hi Eddie,
What’s the current rating on the amp? Going back to my younger years, I remember that amps like that would suck power for a past-time, and always had to be wired direct to the battery.
The other issue you may find is that the DC feed from one of those bricks may not be smooth enough.

However imo the first thing to do would be to check the manual for the current rating needs for the amp.

Personally I think that amp may be well overkill... remember that sound is logarithmic not linear... so 0-10w is lots, 10-99w is little, 100-110w is lots more etc etc..

 

[nugat]

I'd agree that the amp is overkill for a pinball machine, however as you already have it, you may as well make use of it. I would get a separate power supply for it to ensure you don't damage any of you pinball circuitry.

I'm not sure that the sealed transformers you linked would be up to the task, I have used one before in an arcade machine but it was only powering this wee fella....

https://www.ebay.co.uk/itm/500W-12V...-Car-Motorcycle-Radio-MP3-Player/323366178810

(although no way does that put out 500w unless it's on fire! )

For powering your amp I would suggest something like this.....

https://www.ebay.co.uk/itm/12-volt-DC-power-supply-enclosed-switch-mode-12V-18A-240W/221103017605

There are loads on ebay, I'm currently using a smaller version in my pincab for powering a mini audio amp same as the one linked above. They're easily mountable with a couple of wood screws and the case allows plenty of cooling so ensure it doesn't overheat.

 

[Eddie Twadds]

Thanks for input. Have just dug out on old computer psu that knocks out 19a on the 12v rail which should do nicely. If that doesn't work I'll take a look at that power supply.

Overkill....not even close