I'm coming in a bit late on this but if you decide to parallel two or more power supplies, one thing to watch for/be careful of is that the output voltages of the two (or more) power supplies have to be pretty well matched when under load. (There might be an output voltage adjustment.) If the output voltages are not well matched, you will get what I call "current steering" - current from the supply at the higher voltage will source current into the supply at the lower voltage.
The amount of current will depend upon the voltage difference between the supplies and the input/output resistance of the two supplies. (This is due to Ohm's Law.) The supply that is sinking current (the one that is taking in the current) may or may not be receptive to that current that is being "forced down its throat". It depends upon how it is designed. In some cases, you may actually then see its output voltage rise to correspond with the increasing current because the regulator can't sink current (i.e., accept current) well. You may not get what you expect when this happens and if one of the supplies is sinking current, it is not helping you by supplying current to the load, your amplifier.
The usual solution to this is to put diodes in series the output of all the power supplies before the junction where they are combined. This would keep the supplies from sinking current. However, in this case, you are talking about "lots of Amperes", and you would need to find some high current diodes and/or parallel the diodes to meet the current expectations when operating normally.
So, bottom line, if you don't want to go through the whole diode thing, just keep the power supply voltages pretty well matched while under load. You will know that they are matched if you actually see the double/triple current you expect and not somewhat less current at the load.
Topic: Looking for Linear Power Supply (Read 3343 times)
