Hello people,
Can i use my commercial amplifier as a power supply, per example, for my laptop. I mean, if we provide at the input of the amplifier , per example , 700mVdc , then in a perfect world, in the output of the amp should be a dc signal with the amplitude controlled by the volume pot, right ? A good comercial amplifier can provide, per example, continuous 19vdc for a laptop (let's say about 4 A ) ? . If the ampllifier can drive loads of 4 ohm, it should also can power up the laptop, right ? What about if it is not a laptop and if it is a 12vdc led lamp ? It's easier for the amplifier because it's less current, right ?
The tension at the output of the amplifier will be a flat line, with little ripple, or not at all ( it will drop too much )?
Thanks guys.
Can i use my commercial amplifier as a power supply, per example, for my laptop. I mean, if we provide at the input of the amplifier , per example , 700mVdc , then in a perfect world, in the output of the amp should be a dc signal with the amplitude controlled by the volume pot, right ? A good comercial amplifier can provide, per example, continuous 19vdc for a laptop (let's say about 4 A ) ? . If the ampllifier can drive loads of 4 ohm, it should also can power up the laptop, right ? What about if it is not a laptop and if it is a 12vdc led lamp ? It's easier for the amplifier because it's less current, right ?
The tension at the output of the amplifier will be a flat line, with little ripple, or not at all ( it will drop too much )?
Thanks guys.
Yes, but in last ressouce, if i dont have other power supply or transformer, it will work, right ? The amplifier that i have here is 100w 8 ohm per channel... so yes, it will reach 19vdc or 12vdc... And if i, some day, need to do this, i will put a multimeter measuring the voltage at the amplifier output ( i will see the voltage as i turn the volume pot ). I already tried for led lamp of 12vdc... But i tryed with a sine and square wave at various frequecies... the lamp lights and flashes according to the frequency... What i really want to know is if it will work reasonably with a dc signal... Again, in last ressource...
Thank You
Thank You
You would need a rectifier on the output of the amp and an AC signal at the input.
The only way this method could be useful is if you are powering a record player motor built for 50hz on a 60hz supply in order to get the correct speed. A step up transformer would most likely need to be added to the output and you would certainly need an accurate frequency at the input.
We in the UK would have to do it the other way round as our supply is 50hz.
The only way this method could be useful is if you are powering a record player motor built for 50hz on a 60hz supply in order to get the correct speed. A step up transformer would most likely need to be added to the output and you would certainly need an accurate frequency at the input.
We in the UK would have to do it the other way round as our supply is 50hz.
...So if i rectify, i should be able to drive, let's say, loads equal or above 4 ohms, right ? Like powering a laptop, per example...
And in the beginning of the process of rectifying, the rectifying capacitor is discharged, so the current, in that moment, will exceed the maximum value that the amplifier can provide ?, or not ? How do i find that initial current ?
And in the beginning of the process of rectifying, the rectifying capacitor is discharged, so the current, in that moment, will exceed the maximum value that the amplifier can provide ?, or not ? How do i find that initial current ?
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"Audio" amplifiers are almost all DC blocking.
The Crown DC-300 was DC coupled through. (No audio person could need 300W those days, the expected user was test labs.)
It was reported that a user with a dead audio mixer power supply put a flashlight battery to the DC-300 input, trimmed the gain for 15V out (actually +/-15V from the two outputs), and the show went on.
Note that you can pick up power supplies for most laptops often far cheaper than any audio power amp. The popular Dell 19V 6A supply was selling everywhere on eBay (genuine Dell, lightly dusty) for $4 a few years ago. It inspired at least one small-commercial product, as well as the MoFo in the Pass section here. Price has recovered to $6, big deal. If you truly fear laptop supply failure, it seems best to get a few of the "right" supplies, than to risk laptop disaster with an improvised supply.
The Crown DC-300 was DC coupled through. (No audio person could need 300W those days, the expected user was test labs.)
It was reported that a user with a dead audio mixer power supply put a flashlight battery to the DC-300 input, trimmed the gain for 15V out (actually +/-15V from the two outputs), and the show went on.
Note that you can pick up power supplies for most laptops often far cheaper than any audio power amp. The popular Dell 19V 6A supply was selling everywhere on eBay (genuine Dell, lightly dusty) for $4 a few years ago. It inspired at least one small-commercial product, as well as the MoFo in the Pass section here. Price has recovered to $6, big deal. If you truly fear laptop supply failure, it seems best to get a few of the "right" supplies, than to risk laptop disaster with an improvised supply.
Hello, it's not just to powering laptops... I found interesting the fact that i can control the tension with the volume pot... and i found interesting that i can power up several electronic devices in case i don't have power supply for them, and i can use the amplifier as an alternative...
Per example, put 12v led lamps flashing... Make a strobe light perhaps... I like to play with this things ;-)
Per example, put 12v led lamps flashing... Make a strobe light perhaps... I like to play with this things ;-)
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Well its great to play with stuff and 'know it can be done' but you also have to be realistic in knowing what is just for fun and what is do-able in theory but no good in practice.
Take your laptop. Suppose you did set up a 100watt amp that runs on -/+50 volt rails to deliver say 19 volts at 4 amps into a laptop.
Think of the heat the amp will dissipate. It would be around 120 watts. Its just not workable.
Take your laptop. Suppose you did set up a 100watt amp that runs on -/+50 volt rails to deliver say 19 volts at 4 amps into a laptop.
Think of the heat the amp will dissipate. It would be around 120 watts. Its just not workable.
Talking is good. I'm interested about how you are going about trying to learn and your experience with getting information these days, would you mind having a look at this thread here Yet another basic question and please feel free to say anything you like 
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