Class D build

There are a ton of designs out there... Try This

But, if you are used to tube circuits you're going to find this to be very different... to the point where you might not even recognize the circuits.

Most Class D amplifiers, these days, base themselves around one chip solutions and there are tons of them available at surprisingly low prices. The reason for this is that Class D incorporates some very high frequency (for audio) switching that, if not martialled correctly can lead to really bad results. Even the positions of some parts relative to the chips becomes a factor in success. It is rare that you will see a successful Class D amp designed from scratch outside of the engineering departments of corporations.

I hope this helps...
I certainly don't want to scare you off... Class D is where it's at right now.

It's a pretty big leap from Valves to PWM amplification. Perhaps you might consider an intermediate step of buying a couple of cheap TPA3116 based boards from Amazon (etc.) and studying them a bit before proceeding. The TPA3116 chip is a good one and, if it survives (my first couple didn't) I think you will like the sound quality from it, too. They really shine with a 24volt brick style SMPS power adaptor and 8 ohm speakers.

The attached application notes might also be helpful.

It's a very interesting technology.


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  • class-d-audio-amplifiers.pdf
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And just so I know what to research in the future, what would I look for to build a higher end class D amplifier? I.e. what chipset or design.

Right now the TPA311X and TPA325X series chips are very popular and can produce amplifiers up to 300w/ch. There are extensive threads on both in this forum, I think you'll find them very informative.

The data sheets are HERE and HERE

If you're looking for discrete solutions the key is in the driver chips for the switching outputs which have to be carefully managed to avoid overlaps in their on and off times which can be quite disastrous. There are a number of differing chips available for this. The one you use will largely depend on your other choices in design.
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