Simplistic NJFET RIAA

Gonna try a version of Joachims' prefilter with common mode choke after the transformer. This will fed Mur860 then KG 4.7mF, 1R Fukushima, then SSLV with another 4.7mF KG on board. What do you think. Should i throw a nother choke in and drop the R. How do i size the choke? Got boards done. May not get to mounting parts unitl after Christmas with the In-Laws
 
Its good to break some EMI from the rectification. So drop 1 or 2 volts with an R before board's main C if with outboard bridge or by a small hack. Better still is choke input with some leftover speaker air coil.

Took the time to REALLY read you r post. SO you just suggesting a choke after transformer and before onboard cap. If so, Ill bump teh cap up to 10mF KG cap I have on hand and the only option will be the CM choke before rectifiers.

Just simmed a Hammond feeding the 10mF cap and it looks good and comes up pretty slow for electronic world.
 
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Use this config. 2mH air coil plus 20 Ohm in series with it (included with its DCR in the sim).
 

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Loses too much voltage by having no capacitive storage at input. Choke input PSUs in tube audio use a high secondary Tx typically if you look in rectifier valves documents. They usually give choke input and max Cin curves.
 
They dip in the many volts there plus the chokes are in several Henry range. Here it can go off chart. But with a small input cap and a resistor to boost the DCR, the green VC2 output is just a smooth long ramp up/ramp down.
 
I sometimes am too lazy to think about how things actually function, sliding along the surface just building things. Had it working with big 158T, but dropped way too much V, as you said and was pushing its current rating. Ordering two of the hammond transformers and 155B chokes. Will pair with Kg caps that I have. Trying to get brother to bite on Ortofon Vienna cartridge that just went up in Swap:devilr: No reason why i cant njoy it as well.
 
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Hi Buzz

Dunno if you got me...
...I think the cored common-mode is a great GREAT idea...BEFORE the transformer...
...AFTER it you wanna air-core, like Capt. Salas says.

Salas...
...your screen-shot shows a CORED inductor.
( just keepin' you sharp Capt. ( wink )).

Cheers.

Si.

PS...Buzz...see if you can borrow a Geiger from the local high-school or somewhere...
...just a quick sweep of the audiophile 1R's when they arrive should ensure peace of mind.