CRCRC Linear Regulated 24v PSU

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I am new to PCB design and decided to learn KiCad. This is the end result although a few tweaks here and there are still needed.

I have based this PSU on the one built into the Whammy Headphone Amp by Wayne Colburn and I utilised the main CRCRC filtering process but changed the regulation side so the regulator sets the voltage. I removed the dual LEDs for each rail and implemented a single power LED with header to attach your own to mount to a chassis. As you can see in the pic, its dual rail providing both +24v and -24v with a global ground.

With tweaks here and there theres many possible iterations and I will also do a variable output version based on LM317 and LM337.

I am hoping this project will gain some support and interest as the design results in an ultra quiet PSU with practically no ripple.
 

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What is the red part after the transfomer?
A film cap? Better to use Marc Johnston’s Quasimodo R CR bridge snubber
Also the 1N4007 diode protecting the the regulators, better to use 20 ohm in series with 1N4149 diode. The In4149 has less capacitance so less HF/RF feed through and the 20 ohms protects the diode from excess current if it ever has to conduct.
 
What is the red part after the transfomer?
A film cap? Better to use Marc Johnston’s Quasimodo R CR bridge snubber
Also the 1N4007 diode protecting the the regulators, better to use 20 ohm in series with 1N4149 diode. The In4149 has less capacitance so less HF/RF feed through and the 20 ohms protects the diode from excess current if it ever has to conduct.

The red cap at the bridge is a 22uf/250v snubbed cap, X2 rated polypropylene. The design I based from which is part of the Whammy headphone amp is dead quiet already but I would love to try new things and compare the measurements, I'll take a look at your suggestion and see what I can come up with. :)
 
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I used to blindly use big film caps on the secondary, then I tried Mark’s CRC ( cheapmodo tester ) and CRC dampening of the secondary inductance.
It far more accurate, smaller, and quieter. It greatly reduces transformer ringing during diode conduction which is the greatest noise source the DC filter has to clean up. The properly tuned CRC network reduces this to a minimum. It takes just a few minutes with a scope and the tester to find the correct R value and impliment. C1= .01 uf , C2 = 0.15 uf and R varies by transformer. Highly recommended.

As Jean Paul says below there are much better new regulators , while the CRCRC filter works well , you don’t get the best out of it if you use a noisey old regulator
 
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I will also do a variable output version based on LM317 and LM337.

Please don't. There are way better regs available. 78xx/79xx and LM317/337 really are old news. They are way more noisy than their modern cousins. I think they are still used as they seem like a standard part that everybody knows. Maybe nostalgic reasons too, I don't know.
 
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I used to blindly use big film caps on the secondary, then I tried Mark’s CRC ( cheapmodo tester ) and CRC dampening of the secondary inductance.
It far more accurate, smaller, and quieter. It greatly reduces transformer ringing during diode conduction which is the greatest noise source the DC filter has to clean up. The properly tuned CRC network reduces this to a minimum. It takes just a few minutes with a scope and the tester to find the correct R value and impliment. C1= .01 uf , C2 = 0.15 uf and R varies by transformer. Highly recommended.

As Jean Paul says below there are much better new regulators , while the CRCRC filter works well , you don’t get the best out of it if you use a noisey old regulator

The extra RC in the CRC configuration makes all the difference believe me. Its dead silent! :)
 
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