24v supply for amplifier

Thread Starter

dadadiouffy

Joined May 4, 2020
51
Hello people, anybody can advice me, I wanna run my power amplifier which take in 24v 3amp, but I am just having a lot of 12v 1.5amp chargers, is there a safe way to combine 2 chargers to make 24v 3amps?
 

Papabravo

Joined Feb 24, 2006
13,759
Hello people, anybody can advice me, I wanna run my power amplifier which take in 24v 3amp, but I am just having a lot of 12v 1.5amp chargers, is there a safe way to combine 2 chargers to make 24v 3amps?
Why are you running an amplifier from a charger? I don't think they were designed for that purpose.
 

Audioguru again

Joined Oct 21, 2019
1,508
Your Amplifire is not an audio amplifier:
1) Its 700V 13003 transistor is not biased correctly.
2) It needs many output transistors because it is a class-A heater that heats a lot all the time even when it is not playing.
3) It uses a plus 25V and a negative 25V power supply. The negative power supply has an orange wire.
4) The speaker has a high DC current in it which will quickly burn it out.
 

Thread Starter

dadadiouffy

Joined May 4, 2020
51
Your Amplifire is not an audio amplifier:
1) Its 700V 13003 transistor is not biased correctly.
2) It needs many output transistors because it is a class-A heater that heats a lot all the time even when it is not playing.
3) It uses a plus 25V and a negative 25V power supply. The negative power supply has an orange wire.
4) The speaker has a high DC current in it which will quickly burn it out.
Oh, sometime I don't trust YouTube stuff. I did the same amplifier with tripple IRFZ44N then my speakers started to heat up
 

Thread Starter

dadadiouffy

Joined May 4, 2020
51
Many student kids from a country with billions of people post horrible electronic circuits on You Tube that do not work properly. They do it to get paid by You Tube each time somebody looks at the ad ahead of their video.
OK I see, is there a way I can use a transformer without center-tapped on this schematic diagram? and can I use even soft iron transformer?New Picture (3).jpg
 

Audioguru again

Joined Oct 21, 2019
1,508
The center-tap allows the transformer to be part of an oscillator. Without a center-tap then complementary Mosfets (one N-channel and one P-channel) can be source-followers and capacitor-coupled to an ordinary transformer primary with an added transistor making the circuit oscillate. This is not an amplifier.
 

MisterBill2

Joined Jan 23, 2018
6,107
If that is the only thing available, then you have your answer. why do you even have to ask the question?
And I'm not your "bro"!
If you have FOUR supplies, each able to deliver 12 volts at 1.5 amps, then you put two sets of two in series all in parallel and that will add up to 24 volts and 3 amps capability. BUT before any of that you need to use a voltmeter to verify that the voltage from each supply is actually 12 volts. That is because if they are chargers then the voltage must be greater than 12 volts. BUT the circuit shown in post #7 can not ever work no matter what because the circuit is all wrong. AND certainly the speaker will heat up and burn out because there is DC in the coil all the time. I would not ever trust a circuit from you-tube. Look at the circuits posted on a technical website, , such as "schematicforfree" or the "Free information society" websites. On those sites you will find circuits that will work.
 
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Thread Starter

dadadiouffy

Joined May 4, 2020
51
If you have FOUR supplies, each able to deliver 12 volts at 1.5 amps, then you put two sets of two in series all in parallel and that will add up to 24 volts and 3 amps capability. BUT before any of that you need to use a voltmeter to verify that the voltage from each supply is actually 12 volts. That is because if they are chargers then the voltage must be greater than 12 volts. BUT the circuit shown in post #7 can not ever work no matter what because the circuit is all wrong. AND certainly the speaker will heat up and burn out because there is DC in the coil all the time. I would not ever trust a circuit from you-tube. Look at the circuits posted on a technical website, , such as "schematicforfree" or the "Free information society" websites. On those sites you will find circuits that will work.
Ok thanks
 

MisterBill2

Joined Jan 23, 2018
6,107
A switching mode supply is a quite complex system, and not a project for a beginner, or an intermediate. And a rectifier,filter, regulator system does not need a circuit board, it can be assembled on a couple of solder lug terminal strips.
Transformers are always available in discarded failed electronics, usually such are available
 

sparky 1

Joined Nov 3, 2018
186
The overall situation requires overcoming complexity. Too complex for the average DIY.

The specific situation is 24V 4A for stereo.

The question about joining two 12-0-12 transformers was yes it is possibly to get 24V.

The discussion goes silent because of liability and safety. As a result of shortage. The shortage is a result of balanced trade and fair trade without having strings attached that threaten soverienty.
 

MisterBill2

Joined Jan 23, 2018
6,107
The overall situation requires overcoming complexity. Too complex for the average DIY.

The specific situation is 24V 4A for stereo.

The question about joining two 12-0-12 transformers was yes it is possibly to get 24V.

The discussion goes silent because of liability and safety. As a result of shortage. The shortage is a result of balanced trade and fair trade without having strings attached that threaten soverienty.
First, nobody has suggested complexity. Series and parallel connections like I described are not complex.
Second, the request was for 24 volts and THREE amps, not four. What liability and safety issues are YOU talking about????
Third, The transformer availability problem is at least partly due to transformers not being used as much because they cost more than switching supplies cost.
And is Sparky1 even in the same thread???
 

sparky 1

Joined Nov 3, 2018
186
The post in the wrong thread has been corrected.

For myself I recommend 24-0-24 Volt 4 Amp because I feel that for me paying long dollar possibly room to grow.

Having a conversation on the forum that is not UL approved construction. Might be some kids trying that so being careful. First everybody has a life vest and knows how to line up for life boat drill. Young person reading this could be seriously hurt if procedures are not followed. The same with switch mode. The assembled boards are under $10.00. always short out the capacitors using a resistor because handling mains can be dangerous. It is the subject nothing personal. I have seen more than I care to see with stacking power units. Second thank you for your service and may they rest in peace.
 
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