Simplistic MosFET HV Shunt Regs

Hi,Salas
My first shunt is working perfectly.Thanks for suggestions.The sound is not comparable to anything else in range from C-L-C, C-R-C or series mosfet psu.That is simply the music and everything else I tried euphony without dynamics and reality.The 12ax7 does not sound soft and restricted in treble like before anymore .
Now I need to build another one for that 12ax7 phono which now is shared with line amp psu and it consume around 2mA.Which current is desired to be set by R1.Phono is feed with over 1m of cable for a moment and the sound is fantastic.Now I imagine result with short cable so I must try it.
Is there any ccs current minimum regarding performance.I was thinking about 40mA or can I set it under 40?
 
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memo:

If your consumption is 4-5mA for stereo, I would consider 30mA setting as lower ballpark. You would need 25mA for internal consumption and for keeping the output impedance as intended. Congratulations for your results. Its nice you like it. Is it a point to point build? Pictures are welcome.
 
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memo:

If your consumption is 4-5mA for stereo, I would consider 30mA setting as lower ballpark. You would need 25mA for internal consumption and for keeping the output impedance as intended. Congratulations for your results. Its nice you like it. Is it a point to point build? Pictures are welcome.

Salas could I use this information for B+ tube 26 preamp?
 
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HV settings for best performance.

Hi Salas.
I am sure this question has been answered many times before, but if I may: I want an output of 250V at a maximum of 16 m.a.. What would be the minimum voltage to input on the regulator to obtain optimun performances?
Would 35 m.a. be enough in the current department.
I read that bypassing C2 with a 100nf capacitor makes an interesting upgrade. Is there anything else we could do?
Thank you.
 
diyAudio Chief Moderator
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260-265V will suffice as minimum DC input to the 250V reg. 35mA will be enough for 16mA max load consumption. Make it 40mA if you can, its a bit better. CLC pre filtering and a good C2 or bypass, replacing the trimmer with a low ppm resistor after finding the value, a good C3 or bypass, a low ppm non inductive 120K Rref, short cabling to the load, that is about it.
 
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Joined 2009
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260-265V will suffice as minimum DC input to the 250V reg. 35mA will be enough for 16mA max load consumption. Make it 40mA if you can, its a bit better. CLC pre filtering and a good C2 or bypass, replacing the trimmer with a low ppm resistor after finding the value, a good C3 or bypass, a low ppm non inductive 120K Rref, short cabling to the load, that is about it.

The 120K Rref must be 2W or can be 1W or less, I'm asking this info due to the fact it's very difficult to get 2W in only one resistor with low ppm....