You may need something like this, but smaller and cheaper, if you sometimes need to push alot of power.
Hifonics HFC1000 PowerCap 1 F | Conradelektronik.dk
I really dont understand electricity so you may not need it at all. I just know many car-audio enthusiasts put one or more just before the battery input off their amp.
Cheers!
Hifonics HFC1000 PowerCap 1 F | Conradelektronik.dk
I really dont understand electricity so you may not need it at all. I just know many car-audio enthusiasts put one or more just before the battery input off their amp.
Cheers!
Computer Server power supplies are 12v chonkers
FWIW computer server power supplies (not the typical ATX ones) run all their power output as a single 12v out, and are available in huge capacities for cheap. People mostly use them for running high power RC car battery chargers as far as I can tell. It requires some DIY to turn one on (more than the short-the-green-wire method used for ATX) and get wires connected to the bare output plates, but it can be an interesting option. I've used an HP DPS-460EB and the instructions found on this page: Server Power Supply Pinout – Simon Wyss to power an Infinity 310a car amp for a sub, with excellent results. The supply was dead silent at idle (as far as I could hear in my admittedly not-silent room), only spins up the fan as needed and ramps back down aggressively, and gracefully shuts down if overloaded (tested with a car battery tester). I got two of the power supplies for free and gave the other to a friend who is happily running a JL amp and sub with it.
I also picked up a 1100/2400 watt (rated at 200 amp 12v output if you feed it 220v AC, 95a 12v @110v AC) looooong boy, because it was only around $20 and I figured it would come in handy for something. I haven't tried it for anything yet; it might be fussier than the HP, or a screamer.
One of the videos I watched on the subject said adding a capacitor to this sort of setup is completely useless*, simply because a switchmode power supply like this is a constant voltage source. So the voltage never drops (for the capacitor to boost), before the power supply shuts down from overload.
* beyond the discussion of whether boost capacitors help at all in a standard battery and alternator setup. I have heard that they can help with high crest factor music and a limited charging rate. But the flipside is they will hinder modern compressed/heavy sine wave music as they will be eating into the power source as they recharge.
FWIW computer server power supplies (not the typical ATX ones) run all their power output as a single 12v out, and are available in huge capacities for cheap. People mostly use them for running high power RC car battery chargers as far as I can tell. It requires some DIY to turn one on (more than the short-the-green-wire method used for ATX) and get wires connected to the bare output plates, but it can be an interesting option. I've used an HP DPS-460EB and the instructions found on this page: Server Power Supply Pinout – Simon Wyss to power an Infinity 310a car amp for a sub, with excellent results. The supply was dead silent at idle (as far as I could hear in my admittedly not-silent room), only spins up the fan as needed and ramps back down aggressively, and gracefully shuts down if overloaded (tested with a car battery tester). I got two of the power supplies for free and gave the other to a friend who is happily running a JL amp and sub with it.
I also picked up a 1100/2400 watt (rated at 200 amp 12v output if you feed it 220v AC, 95a 12v @110v AC) looooong boy, because it was only around $20 and I figured it would come in handy for something. I haven't tried it for anything yet; it might be fussier than the HP, or a screamer.
One of the videos I watched on the subject said adding a capacitor to this sort of setup is completely useless*, simply because a switchmode power supply like this is a constant voltage source. So the voltage never drops (for the capacitor to boost), before the power supply shuts down from overload.
* beyond the discussion of whether boost capacitors help at all in a standard battery and alternator setup. I have heard that they can help with high crest factor music and a limited charging rate. But the flipside is they will hinder modern compressed/heavy sine wave music as they will be eating into the power source as they recharge.
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Hi ! thanks a lot for the very interesting advice. Lately i have decided to switch to high efficiency speakers ... especialli in my current situation i need let's say more 2 ohm stability than high power.
I will even try this old Xbox psu i am buying (see attachment)
I like it because it is completely sealed
Thanks a lot again
Attachments
Hi ! sorry it's me again. I have got the Xbox psu ... the model is the one in the attached pics. I have the 175W model. i am already looking for the 203W model
I have not cut the plug yet .... i wonder hot to connect the wires to get the +12V and ground. The wires with the same colour can be connected together ? thanks a lot
Attachments
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Thank you ! i think i have found it
How to get output from XBox 360 Power Adapter as 12V 16A Power supply vid: 247-011 - YouTube
the 203W model is very rare ... but i have time We have all the time ... [/url]
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another possible option as psu
Autentico Originale Dell Optiplex DA-2 Series 220W AC Adattatore Alimentatore Caricabatterie | eBay
i am very worried about the need of grounding the amp. Does it mean that i have to run a cable from the mains ground to the amp chassis ?
Autentico Originale Dell Optiplex DA-2 Series 220W AC Adattatore Alimentatore Caricabatterie | eBay
i am very worried about the need of grounding the amp. Does it mean that i have to run a cable from the mains ground to the amp chassis ?
A 12v DC power supply will have two output terminals. One is positive and one is negative. The negative (may or may not be connected to the mains ground) will go the ground terminal of the amp. You don't need any other ground for the amp.
In the US (since others may be interested in this information)...
Most of the plastic cased power supplies have a floating secondary (no connection to the mains).
Most power supplies in a metal case and with a 3-prong mains plug have the ground terminal on the 12v side directly connected to the mains ground.
If I'm not mistaken, when a 3-prong mains plug is used and the power supply has a metal casing, the supply case will be connected to the mains ground for safety, regardless where it's to be used.
In the US (since others may be interested in this information)...
Most of the plastic cased power supplies have a floating secondary (no connection to the mains).
Most power supplies in a metal case and with a 3-prong mains plug have the ground terminal on the 12v side directly connected to the mains ground.
If I'm not mistaken, when a 3-prong mains plug is used and the power supply has a metal casing, the supply case will be connected to the mains ground for safety, regardless where it's to be used.
Thank you sincerely again. I think i have understood now
and sorry for the repetitive questions. I will try first the plastic cased type with no connection to the mains ground (i see a 2 prongs plug).
Next step to try a metal casing smps
I hope i will be able to report on the outcome ...
Thanks a lot again.
Hi ! thanks for the very valuable advice. I am a little scared by the needed modifications to make it work by the way ... but i see many good bargains.
The fact that they are designed and built to run 24/7 says quality.
All models need internal modifications ? is there any model for dummies ?
Thanks a lot again, gino
Server supplies are a good deal and if it will run at 12v (good enough for a lot of different tests) without being adjustable, you have to be concerned about the fans. Some will run the fans at full speed without modifications and some server fans can drown out a commercial jet on takeoff.
I don't have any experience modifying them so I'll leave that to others but be aware that it may be risky (if you don't have an isolation transformer) due to being mains powered.
I don't have any experience modifying them so I'll leave that to others but be aware that it may be risky (if you don't have an isolation transformer) due to being mains powered.
Actually i do not know how much power will i need. Of course the more the better. I have still to receive the amp i bought. As soon as i will get it i will post a pic with the label ... maybe there are power supply requirements on it ?
If i understand well if i have a power supply of let's say 12V/10A = 120VA this is the limit of power i can take out from the amp ? ok less for the efficiency not being =1 ... maybe 100W total ? on which load ? i am very ignorant ...
If i understand well if i have a power supply of let's say 12V/10A = 120VA this is the limit of power i can take out from the amp ? ok less for the efficiency not being =1 ... maybe 100W total ? on which load ? i am very ignorant ...
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DC power supplies tell you the output current that they can supply.
VA is for the AC side, not the DC side. There is no need to be concerned about the power factor. Just look at the output current rating and supply voltage.
That's the power that you can draw from it but amps are typically about 50% efficient at full power (linear amps, switching amps are more efficient) so you won't get 100% of the output power of the supply to the speakers.
Didn't you say that you were using very efficient speakers? People, like those with tube amps, use speakers that can produce acceptable levels with just a few watts.
VA is for the AC side, not the DC side. There is no need to be concerned about the power factor. Just look at the output current rating and supply voltage.
That's the power that you can draw from it but amps are typically about 50% efficient at full power (linear amps, switching amps are more efficient) so you won't get 100% of the output power of the supply to the speakers.
Didn't you say that you were using very efficient speakers? People, like those with tube amps, use speakers that can produce acceptable levels with just a few watts.
Thank you very much again. So i will get about 50% of the power delivered by the power supply at maximum. I see.
That is the plan for the future ... but i do not need much power even now.
What is strange to me is that amp with similar power can have much different bass. I guess bass is correlated to actual current delivery with some amps limited in the amount of ampere that can provide to the load ?
I did a test that left me puzzled. I built a dummy load with 2 8ohm/100W power resistors in parallel (i.e. to get a 4 ohm load).
Then i connected some amps very similar in declared power (about 50W on 8 ohm) to the dummy load.
Two behaved as expected ... they got hot and so the load resistors.
One amp instead got very hot on the heathsink (very) with the resistors remaining cold ..
How can this be ? i still have that amp. I guess it did not like 4 ohm loads very much.
I have speakers that are indeed 4 ohm ... better to try other amps ?
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