Can I use a 2A transformer to power 4 TDA2050 amplifier chips?

[Tesladude]

I will need to supply other things on this project so I think I will need more current but That is a great deal and I will totally keep it in mind.

So you guys were sayin just take out the 1000uf? wouldn't that cause dc related problems?

 

[Baluncore]

If you remove the capacitor then you must go to topology 2, (a split supply), or topology 3, (a bridged pair of chips with a single supply).

 

[meBigGuy]

Personal Opinion here. I think an output capacitor in series with a speaker is a huge degradation of the system performance due to capacitor non-linearities and loss of low frequencies. I like the split supply for its amplifier simplicity, but the bridged amplifier makes sense if a split supply is not practical (ie not cheap nor available).

The currents required are deterministic. The peak current is maximum voltage across speaker divided by speaker impedance. The supply should be able to deliver that peak current to both channels for at least 100ms without limiting or drooping. Most commercial supplies will supply well in excess of their rated current for short durations, just as long as you don't exceed the power dissipation rating.

Do a google search on Amplifier Power Ratings. There are many good explanations and examples.

 

[Tesladude]

Ok thanks guys I think i have everything I need. But just a couple random questions if you don't mind,

On some pre made audio modules or kits I have found that the 1,2.2, or 3.3uf capacitor in seriece with the input are being used with a few 100v capacitors and vet everything else is normal, it is just the input so why would they do that?

In a split supply, and other supplies, you have the decoupling capacitors to stop any supply, but many circuits have like a .1uf cap in parallel with a 220uf decouple cap, what is special about 220.1uf?

Also can I combine a left and right audio output and put them both into the posotive of one speaker to get a speaker that is putting out left and right (center speaker) without doing any harm to the amp or anything?

 

[Baluncore]

They isolate the DC level between modules and so separate the pre-amplifier's front end DC bias from any unknown DC input . With high impedance amplifiers, AC input coupling capacitors can be small.

220uF is a big slow electrolytic capacitor with significant self inductance. 0.1uF is a fast ceramic capacitor. They each handle a different part of the frequency spectrum.

No, you cannot combine low impedance outputs directly. To sum two channels into a single speaker you would need to drive each side of the speaker with a different amplifier, that would require you invert the input to one amplifier only so as to reverse the speaker difference phase.

 

[sophiecentaur]

To put L and R channels into one speaker you need to combine at low power and then amplify. Two low impedance (high power) outputs in parallel will involve impossible levels of difference currents as they 'fight' each other.

 

[jim hardy]

Also can I combine a left and right audio output and put them both into the posotive of one speaker to get a speaker that is putting out left and right (center speaker) without doing any harm to the amp or anything?

There do exist dual voice coil drivers , usually big ones for low frequencies. You could use one of those with one of its coils driven by each amplifier
but little speakers are so cheap why not just put two in one box?

 

[Tesladude]

Ok! Thanks guys!