bombersun

hey, i need some help. i was planning on building an amp rack. i was going to put two computer fans in it. i was wondering do i have the fans blow in or blow out? and how do i hook up the power because there are 3 wires. what are the 3 wire and how do i hook it up?

rcurley55

I've never used computer specific fans, so I don't know what the third wire is. Just make sure that they are 12V DC brushless fans.

From a fluid mechanics standpoint, place the fans a the "inlet" forcing air over the amps with a hole at the other end of the rack to act as an outlet. You could place them at the outlet as well. Just remember, if you put one at each end, you will flow half as much air as you would if you put both on one end.

I would recommend that you use either a switch or your amp remote to trigger a relay to power the fans, do not wire them directly to your amp remote unless you want a fried headunit!!

SDSUlude

Well, my amps are in a box with plexi over them. i have one fan blowin air in on the right, and one sucking air out on the left. But Im not sure if your amps are completly enclosed like mine or not. The fans that I got only have 2 wires. Not sure what the third wire is. Oh, and I used a relay and spliced a wire off of the remote lead to activate the fans when the stereo is turned on.

b00gers

if you have a 3 wire fan...just snip the extra off. but i cant really say which one is the extra one.

the 3rd wire is usually for the motherboard to check the speeds on the fan, RPM.

Kaspin

Should be yellow +12v, black ground and the extra wire is usually green. You can also buy PC fans with only 2 wires.

Hondaman

Correct me if I'm wrong, but wouldn't you want to turn on the fans before the amp comes on to eliminate 'pops'?

94civicEX

I was going to do something like that to my amp rack at one time. I personally think I would have one blowing in and one out, but that's just me :dunno:.