- Joined
- Dec 7, 2012
- Location
- SW Florida
First off, I don't care if I catch flak for this. It's my project, my house, my equipment, and my life. If you don't want to do it, fine; don't.
DISCLAIMER: I, nor overclockers.com or any affiliates are responsible for damage resulting from improper use of a power supply or any other components listed in this thread.
I am quite aware of the dangers of computer power supplies, their limitations, current demands, and proper cooling, however, I am curious to see if anybody else on here has ever re-purposed an ATX power supply to run a car amp off a 120 line.
Seeing as I build electronics all day, I know full well the repercussions of over-current draw on an ATX power supply, but if you do it right there is very little need to worry. When in use, I keep an eye on it at all times and a smoke detector sitting on top of it with a fire extinguisher in the room.
For my application, I modified a 480w/24A/12v AP-P4ATX48F AthenaPower PSU to run a Dual 400w sub-woofer amp. (switched to a California Profile 2000w)
Since the AP-P4ATX48F is a single-rail design on the 12v rail providing a peak of 24A across the rail, I decided this would meet my requirements on the Dual amp as long as I ran it in 2-channel 4-Ohm (50RMS/channel) ensuring that I would never peak out to or above the 24A rating of the 12v rail (assuming their ratings are correct, which I am sure they aren't).
I started out by bypassing the "PS-ON" function and soldered the "PS-ON" wire to an open through-hole ground location on the PCB. This fools the PSU into thinking there is a motherboard attached to the supply and allows it to power up. Since there is already an on/off switch built into the back of the supply, this is all I needed.
The next step involved soldering all of the +12v (yellow) wires together to achieve full current from the 12v rail. [while it is a single rail, the rail is split into about 20 small gauge wires, combining the wires allows you full current from the rail.] All yellow +12v wires were wrapped in electrical tape up to the soldered end leaving the soldered wires exposed.
Once all +12v yellow wires were soldered very solidly together, I did the same for the ground wires. All black ground wires were soldered together, and wrapped in electrical tape leaving the soldered end exposed.
I clipped off the sharp tips on the exposed solder joints, connected the +12v yellow bundle to the + connector on the amp, the black ground bundle to the - connector on the amp, added a jumper between + on the amp and remote to allow the amp to power up, and connected my subs using a 2 channel, 4ohm, 50 RMS per channel setup.
The speakers I am using are two 12" 1300w Sony Xplōd subs, and while absolutely underpowered, they fill my entire room with penetrating bass.
The PSU remains completely cold to the touch after hours of operation, and the voltage only fluctuates between 12.05v (while pounding hard) and 12.5v while nothing is playing.
Overall I am quite happy with how this project turned out, but I will likely end up buying a bench supply that can handle much more current or buy a home theater amplifier in the distant future to power this setup.
Happy modding!
PS: don't burn down your house trying to draw more current than it's rated for. If you have no experience working with or building high-current applications, do not attempt this modification. I am not liable for risk of fire or electrocution that can lead to death or property damage. Always use proper personal protective equipment while handling high-current equipment!
DISCLAIMER: I, nor overclockers.com or any affiliates are responsible for damage resulting from improper use of a power supply or any other components listed in this thread.
I am quite aware of the dangers of computer power supplies, their limitations, current demands, and proper cooling, however, I am curious to see if anybody else on here has ever re-purposed an ATX power supply to run a car amp off a 120 line.
Seeing as I build electronics all day, I know full well the repercussions of over-current draw on an ATX power supply, but if you do it right there is very little need to worry. When in use, I keep an eye on it at all times and a smoke detector sitting on top of it with a fire extinguisher in the room.
For my application, I modified a 480w/24A/12v AP-P4ATX48F AthenaPower PSU to run a Dual 400w sub-woofer amp. (switched to a California Profile 2000w)
Since the AP-P4ATX48F is a single-rail design on the 12v rail providing a peak of 24A across the rail, I decided this would meet my requirements on the Dual amp as long as I ran it in 2-channel 4-Ohm (50RMS/channel) ensuring that I would never peak out to or above the 24A rating of the 12v rail (assuming their ratings are correct, which I am sure they aren't).
I started out by bypassing the "PS-ON" function and soldered the "PS-ON" wire to an open through-hole ground location on the PCB. This fools the PSU into thinking there is a motherboard attached to the supply and allows it to power up. Since there is already an on/off switch built into the back of the supply, this is all I needed.
The next step involved soldering all of the +12v (yellow) wires together to achieve full current from the 12v rail. [while it is a single rail, the rail is split into about 20 small gauge wires, combining the wires allows you full current from the rail.] All yellow +12v wires were wrapped in electrical tape up to the soldered end leaving the soldered wires exposed.
Once all +12v yellow wires were soldered very solidly together, I did the same for the ground wires. All black ground wires were soldered together, and wrapped in electrical tape leaving the soldered end exposed.
I clipped off the sharp tips on the exposed solder joints, connected the +12v yellow bundle to the + connector on the amp, the black ground bundle to the - connector on the amp, added a jumper between + on the amp and remote to allow the amp to power up, and connected my subs using a 2 channel, 4ohm, 50 RMS per channel setup.
The speakers I am using are two 12" 1300w Sony Xplōd subs, and while absolutely underpowered, they fill my entire room with penetrating bass.
The PSU remains completely cold to the touch after hours of operation, and the voltage only fluctuates between 12.05v (while pounding hard) and 12.5v while nothing is playing.
Overall I am quite happy with how this project turned out, but I will likely end up buying a bench supply that can handle much more current or buy a home theater amplifier in the distant future to power this setup.
Happy modding!
PS: don't burn down your house trying to draw more current than it's rated for. If you have no experience working with or building high-current applications, do not attempt this modification. I am not liable for risk of fire or electrocution that can lead to death or property damage. Always use proper personal protective equipment while handling high-current equipment!
they do still work pretty nice 
