Boost the amperage of a small 36v SMPS?

I’m asking a lot of questions about smps and amplifier output output. I have this small unit that is rated at 36v/5a, are there any small things I can change to get maybe 7-8 amps out? The main reason I ask is I see nearly identical units that are rated at 7a. This question is partly looking for solutions to amplifier building and partly for overall knowledge about how these things work.

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Since all the components (including the ferrite transformer) have been designed for the stated output, you would need to change practically everything to end up with a reliable, upgraded supply.
Not very advantageous IMHO, especially if you consider the price of these devices
 
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Fair enough, this is where I got the idea from

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Was wondering if some new caps or something would do the trick. Part of me is a buy once cry once guy and the other part is tinkerer. Maybe I should just get a mean well 500w 36v unit and have a power supply for the foreseeable future. I’ll be building amplifiers for the long haul I’m betting.
 
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As rule of thumb, Usable power is half of the advertised one, even for brand name SMPS. If you have the full specifications datasheet, check out the power derating curve versus operating temperature. Full rated power is only available at 20 degree celsius, then it drops quickly as temperature rises and is about half at any realistic temperature value. This is somewhat also declared on the listing you provided: the seller wrote "Output current: 5A. (work for a long time, need to strengthen heat dissipation)."

To answer your original question: yes it is possible to increase the available power deliveder by your SMPS by adding a beefy fan and maybe increasing the heatsink. The catch is that you will not be able to increase the power draw above the manufacturer rated value, you will only get the power you thought you had available already.
 
The catch is that you will not be able to increase the power draw above the manufacturer rated value, you will only get the power you thought you had available already.

Absolutely. Most SWPS are current limited for self protection. Once you hit the limit value, the output voltage will probably crash to near zero for a few seconds, the amp shut down and perhaps make some nasty pop noises.
Easy to avoid with the right size supply.
 
Always over rate by 50% to get real world results. If you need 250 wats get at least a 500 watt supply. The ratings are usually very optimistic. The closer you run to max output the hotter the ps will get. The hotter it gets the less it is rated for. It’s a catch 22! If you overspec the unit you also have room to grow a little plus cooler electronics last longer. The price difference these days is minimal to get a much better supply. In general, get more or better than is require, that way you won’t be buying another unit because the one you got died or just didn’t do the job.
 
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One of the problems with SMPS for audio is that it doesn’t draw a continuous DC current. It is continuously varying between zero (or some low value) and the DC volts divided by the minimum speaker impedance. You have the average heating to deal with, AND the peak current demand. If you size the supply just for the average demand it can go into a limiting mode on you with heavy bass - on every cycle - and it usually doesn’t sound too nice when it does.
 
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For a 5 - 10 dollar difference, you are using up everybody's time.
That is all the difference in cost between 5 and 7A supplies.

The Ferrites will burn out, and there may not be room on the board for larger caps, so not much point in trying to boost output.
Even the switching transistors and so on will get over loaded.

Just buy the higher rated unit, or like me, buy and old amp and service it properly.
You will get a beefy linear supply, and large capacitors, and for a very low price.

Can't expect a small car to do the work of a truck.
 
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@Lawnboy
@thirdicomplex

You could run 2 power supplies (or more) in parallel to increase performance.
Search for "switching power supplies connected in parallel with passive current sharing". And definitely don't forget the diodes to prevent a possible reverse flow of current, otherwise...
But please do not try to generate a symmetrical +/- voltage with 2 of these power supplies. This does not work with switching power supplies that have a ground reference.