50 VDC power supply

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Hi folks!!
I'm new and don't know very well about electronic but it's my hobby. Recently I have purchased an amplifier circuit (Sat516BE) from eBay that requires 50 VDC regulated power supply. Unfortunately I don't have any DC power supply like that but I do have a toroid dual ac (34-0-34) transformer. My question is can I use rectifiers and capacitor to make a DC supply for it? After I made the DC supply it is giving me exactly 48vdc (x1.41). Should I use it? Kindly help me out guys. I do have another ac transformer rated 48 vac but after I use capacitor I'm getting x1.4 times more voltage through it. Your advice will be appreciated guys. Thanks
 
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34 volts AC gets you close to 50 V DC as you have found out, however its not regulated. The 48 volt transformer would get you close to 70 V DC which could then be regulated down to 50 volts with extra circuitry.

Tbh, there's not enough information to advise... such as why it needs to be stabilised and whether its a single rail or dual rail design. How much current does it need? That is important once regulators come into the equation.
 
Any well designed amp will be tolerant of some supply voltage variation, however your measured voltage is presumably "unloaded". Once you connect a load (your amplifier) it will fall further.
It's unusual for an amplifier to require a regulated supply. It may be that they are saying 50V max.
I would try it with the lower voltage transformer and see what happens.
 
A 34V-0-34V transformer can be used with a single diode from each 34V terminal to form a power supply giving close to 50V. Make sure that the voltage does not exceed the maximum voltage of the amplifier board even when idle and with a maximum transformer input voltage. If the power of the transformer is sufficient I cannot tell you without knowing the "VA" of the transformer.
 
The amplifier is asking for single (vcc and gnd). So what ever I'm getting after adding capacitor (x1.41) that is not real voltage? And should not harm to my system? Thanks you for your's reply guys.


As long as the supply voltage at no moment exceeds the maximum supply voltage the amplifier board can handle, the amplifier board will not be harmed by the supply voltage. The question that remains is how stable the supply voltage will be and that depends on the power capacity of the transformer ("VA"). Could you eventually post a photo of the transformer label giving the specifications?
 
I propose this coupling of the transformer.
It is effectively full-wave rectification but for a single output voltage from symmetrical secondary windings. The windings are conducting alternately such that you have less than 400VA at your disposal. Each winding has 200VA and that coupling will leave a power in-between 200VA and 400VA.
It is still enough for your amplifier as long as you use 8 Ohm speakers.
 

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PRR

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...purchased an amplifier circuit (Sat516BE) from eBay....

You mis-typed. I think you bought STA516BE.
2 X 500Watt Class D Audio Amplifier Board -STA516BE | eBay

This is rated 2x500Watts!

At 3 Ohms. At 10% THD.

It is clearly class D and, like many such amps, is bridge mode.

If you only use 8 Ohm loads, it is likely to really deliver 2x120W, and a 270VA transformer will be fine, especially for UN-clipped speech/music.
 
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