OK, looks like I made a fundamental mistake in the estimation. The important thing is, it's 100% dual mono, two separate amps, one enclosure, so have ample A.
OK, I have it. I read they sometimes use desktop cpu's for home appliances just because they get them for cheap.If this would make sense, is up to you, and the circumstances.
There are situations and circumstances at this world, which
could rearrange someones mind to find this useful.
You don´t have to do that.
You'll have to pardon me mchambin, as I wrote above, the amp is not documented, and I have no experience with power amps. Besides, it concerns me the psu caps are rated 63V. Say with 0R5 resistors in output it drops to 61V, that could be below the tolerance for it in idle.
About the volume, I could limit the max volume in the input.
No problem. I do understand, this is why I gave a general answer.
I would not worry much about a 10% over voltage.
Caps have safety margins, as well as everything in a decently designed amplifier.
10% over voltage is in theory 20% over power, everything else being the same.
20% more power makes 20% more temperature difference over ambient.
As long as transistor heat sinks do not feel too hot you'll be fine.
Wait for other's advice about my cheating with voltage.
A simple way to drop the voltage is a string of diodes. 0.7V per diode.
Wouldn't that make the PSU no longer linear? A very rough estimate I made showed the V on the diode will swing between 0.6V-0.8V assuming the A will be 0.1A-2A, which is already enough to make the V change 0.4% - see this example diode characteristics:
http://docs-europe.electrocomponents.com/webdocs/0800/0900766b80800ea6.pdf
Why not lower the V slightly using a 0R5?
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Linear PSU is just a word to say it is not a switched mode PSU.
The rectifier of a "linear" PSU is made of diodes that drop the output voltage, adding diodes would drop more.
Droping with a resistor is fine too.
Droping with a diode makes the drop about constant versus load current.
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In case you go dropping voltage with diodes and/ or a resistor....of course you put it between the rectifier and the filtering cap(s).
This will make the cap happy with less current ripple and it will thank you with a smoother output voltage.
Be aware the droppers will waste power turned into heat. W = PSUcurrent x Vdrop.
This will make the cap happy with less current ripple and it will thank you with a smoother output voltage.
Be aware the droppers will waste power turned into heat. W = PSUcurrent x Vdrop.
1n5401 has a 3A maximum continuous current.
If your continuous DC current is well below that, then OK.
When you have a very low continuous DC current there is a big reserve for transient current. Well in excess of 3Adc
The 1n5401 will easily pass 6Apk as short term transients provided it is cold, or only warm before that peak.
The datasheet shows an enormous peak transient.
From a starting temperature Tj=25degdees C and for a 1shot pulse, they state 200Apk
If your continuous DC current is well below that, then OK.
When you have a very low continuous DC current there is a big reserve for transient current. Well in excess of 3Adc
The 1n5401 will easily pass 6Apk as short term transients provided it is cold, or only warm before that peak.
The datasheet shows an enormous peak transient.
From a starting temperature Tj=25degdees C and for a 1shot pulse, they state 200Apk
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