Hey guys
I think the power supply must be the hardest part in building an amplifier, power transformers are expensive and hard to come by, however old computer psu are readily available.
The highest voltage we can obtain from a ATX PSU is +-12V, which translate to about 36W into a 8 ohm load with bridging. the +12V line can source at least 10A, however the -12V can't even sink more than 1A.
What I've doing is that, I'd open the power supply and trace the -12V all the way back to the power transformer, then I would connect a pair of high current ultrafast diode (cathode to the two transformer output, anode gets connected together) to the 2 output of the transformer. after that you'll need to connect an inductor to the common anode of the rectifiers (I use the inductor on the 5V line from another ATX PSU), then you can use it as your new -12V line, it should be able to sink as much current as your rectifiers can substain.
To go a step further, most ATX PSU have trimmers on them where u can adjust the output voltage to about 14V (after than the over voltage protection trips, it can be disabled however, but then you need to replace the capacitors on the output stage if you don't want them to blow up, I've seen people modified them to +-24V power supplies)
Okay, that's just a little bit of my experience that I would like to share with you guys, I thought it might help.
I think the power supply must be the hardest part in building an amplifier, power transformers are expensive and hard to come by, however old computer psu are readily available.
The highest voltage we can obtain from a ATX PSU is +-12V, which translate to about 36W into a 8 ohm load with bridging. the +12V line can source at least 10A, however the -12V can't even sink more than 1A.
What I've doing is that, I'd open the power supply and trace the -12V all the way back to the power transformer, then I would connect a pair of high current ultrafast diode (cathode to the two transformer output, anode gets connected together) to the 2 output of the transformer. after that you'll need to connect an inductor to the common anode of the rectifiers (I use the inductor on the 5V line from another ATX PSU), then you can use it as your new -12V line, it should be able to sink as much current as your rectifiers can substain.
To go a step further, most ATX PSU have trimmers on them where u can adjust the output voltage to about 14V (after than the over voltage protection trips, it can be disabled however, but then you need to replace the capacitors on the output stage if you don't want them to blow up, I've seen people modified them to +-24V power supplies)
Okay, that's just a little bit of my experience that I would like to share with you guys, I thought it might help.