Building a 1000W @ 8ohms class D amplifier from zero

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I think there is error here, since lower one has 12v, I assume other will have it too

Hello Luka,

But it should work with 5v also.
From IRF data sheet Vdd (logic supply voltage) max value is Vss + 25V.
Hope that I am right because I started to try to develop SMD PCB version for it :p
Attached is the ongoing PCB version. It still need the output filter stage, feedback, supply filtering, top and bottom ground planes and a buffer at the input because i think i have to drive it with a differential op-amp with one out 180 Degree shifted from the other.

Please correct me is i am wrong. I am new kind of new in this field.

Best Regards,
Savu Silviu
 

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Greetings :)
First, it should be noted that I am n00b, therefore nobody has to point out how stupid I am, because I previously knew that. :p
Second, I have a college education in electronics, however though it went over some theories of amplifiers, no classes concentrated specifically on that.

Now, here is my subject:
I have recently purchased two speakers.
They are simply single drivers, I have yet to build a box
The frequency range is 22Hz ~ 4kHz
Resonance is 22Hz
RMS power is 1000 watt, per speaker
Peak is 2000 watt, per speaker
Size is 21" diameter
They are each 8 ohms :att'n:
I am having a lot of trouble finding a production amplifier that can supply 1000w RMS per channel at 8 ohms and 2000w max at 8 ohms. Most amps barely make 1000w RMS at 2 ohms. Of course that doesn't work with an 8 ohm load. These drivers being 8 ohms is what makes this a bit more complicated. I have two of these speakers, therefore a two channel amp needs 1000w RMS per channel at 8 ohms. If a production amp exists for this particular speakers, I have not yet found it, but I did find this thread in google search, because it mentions 1000w into 8 ohms. I have read this thread from first to last post, but still not sure if the designs posted here will fit this application. I saw some posts that do not believe 8 ohm 1000w speakers exist... but they do, I own two of them. I also read some about the frequency, if I understand correctly, these amps do not go down to 22Hz? My primary operating frequency range would be between 22Hz~400Hz probably. Is there a design currently good for this application?
Many thanks for help on this subject :D
 
You can build a class d amp with a few bit and pieces.

Triangle wave generator and input amplifier both going into a comparator.
The output of the comparator is level shifted into an xor gate to phase split the pwm and then put into a IR2113. The output of the 2113 drives a pair of MOSFETs.

Mine worked a treat although for some reason I needed a DC offset adjust on it.

I did not use any feedback, it is totally feedback free.
Sorry but it is very hard to read,
An externally hosted image should be here but it was not working when we last tested it.
 
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