Remote power switch

[d_sinsley]

Hello,

I am building sub box/amp rack combo for my daughter. Both the sub and the amp will be integrated into one box system. There will be an isolated sealed box for the sub and a separate amp rack but all will be incorporated into one unit. Basically the front of the box will be divided in half with the sub on one side and the amp on the other. The face frame will be 15" high and 32" wide made out of 3/4 MDF. But I am going to cut out two 13x 13 holes in the face, route and inlay two 14.5 X 14.5 x 1/2" plexiglass panels from the back. These will be glued to the frame with Liquid nails to adhere them and seal them then the frame and plexi will be predrilled and glued and screwed to the box. The sub will be mounted to one and the amp will sit behind the other. (BTW this will only be feed with 140W RMS so I am not two worried about the thickness of the plexi and it will be stiffened by the 3/4 MDF, hope my theory works). I say all this because I realize you can not safely enclose an amp in a tight space obviously because it will overheat. So in order to do so I am going to cut a vent on one side of the amp rack and install three CPU fans to the other side to draw air across the face of the amp and the back of the amp will be exposed but unseen.

My question is this, I want the CPU fans as well as the lighting effects that will be inside the speaker enclosure and the amp enclosure to come on when the amp comes on. Is there a switch that can be wired in using the remote wire from the deck to the amp (blue wire) that will then let me draw off the main power coming in to feed the amp? Said another way I want to run the power in from the battery to a splitter block. Then feed the amp and also feed the lights and CPU fans. I would need a switch that is operated off the blue wire which I would split so it feeds the amp and the auxiliary switch. That way when I turn the stereo on the amp, CPU fans, and lighting would all come on at the same time. Do they make such a switch? Is there a better way?

Devon

Click to read more...

 

[bbeljefe]

You need a relay and that relay needs to turn on the amp, the fans and the lights. It will be triggered by the remote turn on wire from the amp.

Watch this video on relays:



If you need more help with the turn on circuit, let me know. I can even pre wire a relay for you to make it easier. But whatever you do, DON"T run fans directly from the head unit's turn on circuit, as you will most likely exceed it's maximum current capacity and damage it.

 

[basswiigee]

Got mY sh!ts on a good ol' fashion taco switch up front!!! Lol but listen to this guy he sounds like he may know something!!! ^^^^^

 

[basswiigee]

...and by the way we want some finished product pictures..... Maybe even videos... The build intrigues me....

 

[d_sinsley]

Thanks for the help. I figured a relay would be the way to go. I am familiar with them and figured this would be the way to do it. I know the remote turn on wire was not enough to feed them. It is just a remote wire to trigger an eternal relay in the amp, so I knew that would be a no go. So a relay it is. If the box/amp work as well in reality as it is in my head it will be cool. 10" sub mounted to a clear front with purple lights in the interior of the box and the amp in an enclosure with clear front also light by purple lights. Should be pretty cool looking. Only concerns are over heating the amp which I think three 80 mm CPU fans cooling the front of the amp and the back being exposed to the air will keep it cool. The other concern is flex of the 1/2" plexi. This sub/amp combo wont move giant volumes of air. 140W RMS is not much power to a sub, plus the plexi will be supported by the 3/4 " face frame and then sandwiched between the fram and the box. The whole rest of the box will be 3/4 MDF. I don't think it will have to much flex to notice much sound quality degradation. I will take pictures or a video.

 

[bbeljefe]

If you're using ½" plexi with that power... there won't be a flex problem. You could (and I would) build the whole thing out of ½ MDF. It would allow for more internal volume and it would be lighter and a bit less expensive than 3/4. Plus, a lot of what you're building is amp rack and to be sure, a small amp rack doesn't need to be that thick.

Also, two fans in a push pull configuration will move more air than three pushing or pulling and, it will be quieter.

 

[d_sinsley]

thanks for the recommendation on the two fans in push pull. I like that better, hadn't thought of it. As for the 1/2 vs 3/4 MDF... as you have noticed in other threads I may go with a bit bigger amp say up to the 250W RMS of the fosgate 250 @2 ohms. Would 1/2' MDF still be adequate. Building it out of 3/4 is not a big deal and I tend to over kill in my design.