Thread: How To: Power 2 Amplifiers With A M2-ATX

Originally Posted by Curiosity

A relay requires more current than an amp. A transistor simply increases the current. Here's a better schematic.

Wow, perfect curiosity....thank you so much. Do you see any reason I couldn't wire this up inside my case at the PSU? I will give this a whirl in the next day or so and report back. Thanks again for all your help!

Sure, as long as it doesn't short to the case or anything it should be fine.

You could probably even solder it to the board itself.

Well just for the sake of it, I tried connecting two Alpine amps to the amp turn on lead, with diodes inline, just to see if it would work. And oddly enough, it does turn on the amps like it should, but when I turn the key OFF the amp's both stay on for another 5 to 10 seconds before they shut down. This behavior doesnt happen when just one of the amps is connected.

That's because you have 2 different Alpine models, and one has a capacitor on it's remote signal. The diode is keeping it from draining back into the M2-ATX. That also suggests that it requires little current and should work better without the diode.

Originally Posted by Curiosity

That's because you have 2 different Alpine models, and one has a capacitor on it's remote signal. The diode is keeping it from draining back into the M2-ATX. That also suggests that it requires little current and should work better without the diode.

You know, now that you say that, I remember reading for one of the amps a "delayed on" so that makes sense. I forget which one though. MRP-F300 or MRP-M500.... eitherway, when I get more time I'll wire in the transistor as posted above. That should do the trick

Hey we87, any updates??

I am about to grab some transistors tomorrow and do the same because I'm having the same problem with my setup. Did it end up working?

Yeah, worked just fine

Originally Posted by Maheriano

EDIT - I'll explain it briefly here.
The pins are numbered and the numbered diagram is on the back of the packaging. But one pin is labeled as COLLECTOR and that will take the input from the power supply. In my case it's the J6 connector on the M2-ATX. Another pin is labeled BASE, this is power from the battery of the car. The last pin is labeled EMITTER, this sends the power out to the amplifiers, split the wire and run it to each amplifier. Done.

Originally Posted by Curiosity

The collector should be connected to the supply (battery) and base to the switch (amp remote on PSU). Any of those transistors will work. For lower current drain on the PSU, a 1K resistor should be placed between the base and PSU.

So which one is correct??