The switch-mode power supply is SIMPLE 

Did they go anywhere?

PirateKitty No, he just didn't mentioned them in the last video.

I just saw a video about JLCPCB. Big ass operation.

o voltagecy for that case alsiYou must wat h current and frequenx

use easy eda website

Once you are in easy eda and you have created your pcb then you click file and click create gerber file, then go to jlc pcb app and and click upload gerber file and clik the previously saved gerber file and click upload

Where does the output stop? Did you go through from the end of the circuit and see step by step? Are you having output on your 2ndary windings on the coil?

You need a diffrent transformer and a lower voltage and higher capacity mains smoothing capacitor

For example instead of 400v 100uf you should use 200v 400uf (4 Times the capacitance)

Thank you very much and I have a room full of old computer power supplies they will work. There's a switch on them for 120~240 but some have no adjustment so they have to be the 120v and I learned my lesson with a Breeze Audio, it had 8 24v 330uf caps and it said to use a 24v power brick and it popped the caps and immediately thought to get 35v 470uf caps they was taller and still fit. I figured that the caps would have a easier life with more reserve. Sometimes it has to be specific to a point. I'm building a different kind of power supply for a Bluetooth speaker box, I have two 100watt amps the one with Bluetooth is stereo and I'll use that for the tweeters mids and woofer and wire the signal to the other amp which is mono which I'll use for the woofer. I ordered a active crossover stereo to mono they're both 24v each and draw around 5a or less. I'm using a center tap transformer with a beefy full bridge rectifier and two 50w 10,000uf caps and a resister to smooth out the noise floor, I'm hoping that works, but I don't know what value resister I should use between the pos and neg? Thanks for your time.

The center tap transformer is 24v-0-24v 5a but adding the caps should give me a few amps, right?

You can use two 200v capacitors. (for ex. 125uf) The switch could connect them in series or in paralel. This way you can use with either 400v 62.5 uf or 200v 250uf. There is a capacitor smoothing formula. You can use it to calculate the capacitance you need.

Replace the AC mains four rectifier and filter capacitor input into a voltage doubler using two diodes and two filter capacitors.

Swap out the transformer

5 times, at the very least.

Bigger capacitors amd power resistors

Why use improper components at all? I don't understand why they show an inaccurate way to begin with like the use of a protection board on a 2P 3S Two in parallel and three in series with a high drain drill without balancing. I'm not a pro, but I've been there with my complaints like the BMS without balancing will charge to full capacity, but the cells have some under voltage and overvoltage which leads to an early death of the battery pack.

You need a proper BMS, that's for sure.

Maybe you lack basic electronic skills!

This is explained at 10:46.