Hi jarthel ,
If you have a regulated power supply like the schematics
shows up , you don’t need to use a CHOKE INPUT FILTER ,
If I was you , I'd prefer a CAPACITOR INPUT FILTER ,
with a 47 uf x 450 V , before the choke , and after the choke
a 100 uf x 450 V . If you want more reliability and more
velocity from your power supply , you can use at the input
( in the place of 47 uf x 450 V electrolytic ) a motor run
capacitor ( polypropilene ) rated for 380 Volts AC .
The Solen capacitor is very expensive for this purpose !!
Carlos
If you have a regulated power supply like the schematics
shows up , you don’t need to use a CHOKE INPUT FILTER ,
If I was you , I'd prefer a CAPACITOR INPUT FILTER ,
with a 47 uf x 450 V , before the choke , and after the choke
a 100 uf x 450 V . If you want more reliability and more
velocity from your power supply , you can use at the input
( in the place of 47 uf x 450 V electrolytic ) a motor run
capacitor ( polypropilene ) rated for 380 Volts AC .
The Solen capacitor is very expensive for this purpose !!
Carlos
thanks for the reply 
I already have a 100uF ASC I was planning to use but these are quite rare to find so I was wondering if I can use the solen instead.
I also need to use choke input as target B+ is 150V and my transformer is a 230VCT. 230VCT into a cap input = lots of voltage to drop! :|
thanks everyone for the help
I already have a 100uF ASC I was planning to use but these are quite rare to find so I was wondering if I can use the solen instead.
I also need to use choke input as target B+ is 150V and my transformer is a 230VCT. 230VCT into a cap input = lots of voltage to drop! :|
thanks everyone for the help
.
I beg to differ - I use an almost identical setup and the superiority of choke input over cap input is quite clear even after regulation.
I use only 10uF and it works fine and also allows you to use a really good cap (quality is more important than size in this application). The shunt reg can be easily improved by using the tube for AC reg (feed +ve rail back into tube grid via a cap) and the TL431 for DC.
I was confused about the L-C filter in a regulated PS, the choke will reduce dynamics if that's something you're concerned with. For me it's either PI filter if using a tube rectifier, or a SS recrifier with regulation. But, my favorite is a tube PS with SS regulation and low uF capactiors, no choke with regulated ps - that doesn't sound good for some reason, just slow and cloudy.
If you go too high on capacitance, this can affect dynamics as well. Depends on whether you using a highly eff toroidal or a warmer EI transformer, as to what you're best bet is for capacitance levels in the PS. Why not just add two more C-R-C filters prior to the regulator. This will reduce the ripple much more than the choke, and you don't have to do much more than a few 30 to 47 uF caps with 50 ohm resistors.
Remeber, this may be the best for your circuit so MMV.
If you go too high on capacitance, this can affect dynamics as well. Depends on whether you using a highly eff toroidal or a warmer EI transformer, as to what you're best bet is for capacitance levels in the PS. Why not just add two more C-R-C filters prior to the regulator. This will reduce the ripple much more than the choke, and you don't have to do much more than a few 30 to 47 uF caps with 50 ohm resistors.
Remeber, this may be the best for your circuit so MMV.
Just use your regulator to drop the excess voltage. You'll be ahead doing this. Just use a larger heat sink, or do two regulators dividing the load. This works much better than the choke, and costs less. The results will be better in terms of bass impact and solid regulation. Will produce some heat, but will worth it.
.
My experience is entirely the contrary, especially in the bass area - I find LC far superior to CLC or CRC (a small cap before the choke to fine tune B+ is OK). However I concur with your comment re excessive capacitance.
jarthel, the improved shunt reg schematic is shown in a Tubecad article. If I can locate it I will post a link.
pm
My experience is entirely the contrary, especially in the bass area - I find LC far superior to CLC or CRC (a small cap before the choke to fine tune B+ is OK). However I concur with your comment re excessive capacitance.
jarthel, the improved shunt reg schematic is shown in a Tubecad article. If I can locate it I will post a link.
pm
jarthel,
the improved shunt reg circuit is shown in the attached link. Sound quality is highly dependent on the quality of the cap bypassing the TL431. I ended up using a Black Gate FK as nothing else came close. The circuit you posted sounds very 'tight' (in the manner of a high nfb SS amp) in comparison. The improved version lets the music 'breathe' a lot better.
Good shunt reg tubes for moderate current applications include the 12B4 and 5687.
pm
the improved shunt reg circuit is shown in the attached link. Sound quality is highly dependent on the quality of the cap bypassing the TL431. I ended up using a Black Gate FK as nothing else came close. The circuit you posted sounds very 'tight' (in the manner of a high nfb SS amp) in comparison. The improved version lets the music 'breathe' a lot better.
Good shunt reg tubes for moderate current applications include the 12B4 and 5687.
pm
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