DIY Class D Audio Amplifier

Thanks to EasyEDA for sponsoring this video.

Aliexpress:

In this project I will show you why a class AB amplifier is pretty inefficient and how a class D amplifier on the other hand improves this efficiency. At the end I will show you how we can apply the theory of operation of a class D amp to a couple of common components in order to create our own DIY class D audio amp.

Music:
2011 Lookalike by Bartlebeats

[MayankJaintheswag]

I honestly love your diagrams, ur handwriting and diagrams are so neat!

[rontan]

I simply love the way he drew everything so neatly, so pleasing to watch that I could watching it all day! =D

[invidios]

I dont know why i'm here, but i didn't skip every single seconds till the end. This is why YT should exist.
Great work!

[LazerLord]

You don't happen to have an old set of cabinet speakers lying around, do you? It's amazing how much an enclosure can increase the sound output of a speaker.

[MichaelOfRohan]

This is the ultimate "what I had lying around" build. Love the parallel capacitors. The end product looks retro i like it!

[gokwyeu]

I have followed this video to build a class D amp. There's some thing you should know if you also want to follow this video.
the 1nf capacitor at 555 timer is used to convert square wave into triangle wave. In my case 1nf is to small to fully convert the square wave, you should hook up a oscilloscope and swap a few different capacitor until you see triangle wave.

R3 (2k ohm) is used to control the frequency at which 555 timer oscillate. I'm not using TLC555, instead I use NE555, in which case the frequency is only 2k Hz if I use 2k ohm resistor for R3. To solve this, you simply replace R3 with a 10k potentiometer, and see what resistance is required to get 200k Hz.


I added a 1000uF capacitor in series with the speaker as a coupling capacitor to block the dc at output stage.

Any way, thank you @GreatScott! for making all the awesome videos about electrical stuff. It helped me a lot. Keep on

[DullPoints]

I wish I knew what you were talking about, but I love watching a knowledgeable person work.

[willwahlberg]

I am amazed at your organization on your circuit boards. It requires so much precision.

[zdw]

I love seeing those Manhattan circuits! So beautiful!

[mohammedmokhtar]

Hey Scott, make a long range radio transmitter and receiver, and maybe show us how to calculate its range. That'd be fantastic!

[albertlee]

The explanation of Class D amplifier is excellent. I have built Class A, B and C amplifier in the past. I own several cheap Class D amplifier today. This video explains clearly of the theory of operations. You have excellent soldering skill as well. Keep up the good work!

[tobywenman]

I just sat my GCSE systems (electronics) paper and you have had a huge impact on my understanding and revision. Thanks!

[misperry]

great explanation! I love the detail of the circuit layout and values. Good job. we need more audio circuitry here on YouTube​.

[hectorguevara]

I must congratulate you. I have an electronics degree, and appreciated the way you explained the theory behind every step you took.

[Darieee]

Insanely polished videos .. I can't even imagine how much it must take to get these done .. Thanks !

[barbasbandas]

is awesome to be working on some audio circuits and receive a notification saying "class D amp" from great scott! made my day

[aldwinvicente]

Great video Scott, may I request a video explaining how to read and apply characteristic curves/graphs and technical table spec sheets of semiconductor devices such as transistors and diodes to constructing circuits? Because I got confused in some parts of the video wherein you made use of those curves and tables but I didn't understand why those values mattered and how to interpret them in the way you did. Also, may I suggest when displaying those curves/graphs to not show them at a dutch angle? It seems a bit difficult to interpret at first viewing. Thank you for all these very technical but non-jargon heavy electronics videos, they're quite insightful. Hope to hear more from you Scott.

[zaldstudio]

I'm here for the glorious drawing and handwriting!

[adityag.]

The 'i'll see you next time' at the end is so calm it relieves all my stress and anxiety

[BADALICE]

I have not even started the video, and I already know I'm going to love it, and definitely build it. This is exciting.
Sweet.