Juma's Easy-Peasy Capacitance Multiplier

Gosh, this thread has a lot of content and quite a few different versions/PCBs!

To hopefully take a shortcut...

I'm starting to work on a project based on X's LuFo Lite design (possibly a SuSyLu Lite?) and I will be designing my own PCB for the actual follower section. I plan to use some SMPS bricks for the power supply but want to use a Cap Mx as X does - in that context, the positive half of this appears to be the best Cap Mx option from the various boards featured on this thread?

https://www.diyaudio.com/forums/pow...sy-capacitance-multiplier-76.html#post6031533

I assume just hook up the SMPS to the input of the PCB without needing the bulk cap? Do I need the bulk caps on the output side?

Thoughts? Cheers.
 
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Sorry I can't help you Ray. It does seem quiet on here and I never sussed out my 1v variance issue on a dual rail build.
Hope you sort it but I don't think I saw a single rail version other than half of one of those ones I sent you. There was a quick schematic for a single rail one for a guy doing P2P somewhere nearer the end of the thread.
 
I plan to use some SMPS bricks for the power supply but want to use a Cap Mx as X does - in that context, the positive half of this appears to be the best Cap Mx option from the various boards featured on this thread?
I had some Cap Mx boards made to be fed by two SMPS supplies for +/- voltage rails. I have decided on this version by Gtose and Mark Johnson:
Juma's Easy-Peasy Capacitance Multiplier
Here are the upgraded Gerber files:
Juma's Easy-Peasy Capacitance Multiplier

I am surprised that my friend, Skylar88, has not replied yet. He used two of these PCB's with two Meanwell supplies for dual mono for his recently built M2 amp. They work very well. I have not populated my boards yet.
 
Folks,

After kindly being donated a few boards here, I've read the thread through, a lot to learn and I suspect not all of it has sunk in. BUT can I ask a question here - I want to drop a little more voltage than the standard 1k pot is giving me. Is there a way to get a bit more adjustment down? Another 3 or 4V down would do the trick for me.

I'm using an old but beefy transformer for a build, (37VAC) and I have about 43V DC at the bottom of the range. I need to get to about 35-38 V if at all possible for the amp circuit that its to power.

And if I might be really cheeky and ask another question of the collective wisdom - is there any benefit in a CRC stage after the cap-mx? The amp is a chip amp, so its not a constant class A current draw.

Fran
 
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So answering my own question possibly we can have no less voltage drop than the mosfet gives but we can trim that voltage a little to balance to the other rail?

Ray, most of these boards have 2 pos and 2 neg rails...4 separate cap mx 'set ups '. Maybe you could hack a board and feed the out from one cap mx into the 2nd cap mx....=8v drop..?!
 
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I think the 2SC5200 is a BJT and therefore 2v drop? A mosfet would give a 4v drop....from what I have read but I'm far from well informed on this!
I don't know if your circuit is reconfigurable for a mosfet.

What about adding a coupe more monolithic bridge rectifiers to loose some V? Not a pretty solution but might help.

What chip amp?

My cap mx board (+ve) was going to be for a tda8932 at about 30v. Needed 50v caps which I overlooked!