The simplistic Salas low voltage shunt regulator

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Yes... I understand that we must not use Rubycon ZA/L there but Silmics and cerafines might do good.

Silmic has that wonderfull bass / upper bass but adds some grit to the sound.... Cerafines might be very good.

As for the BG.... it is still burning and getting better over time so I will wait.... nevertheless BG are almost unobtainium so we must search elsewhere.

Ricardo, Michael Percy Audio U.S.A. still have BG 47uF

160V VK series
16V FK
25V PK
16V, 50V & 100V Standard
 
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I am already working on that.

i am actually using BG for the 47u but I will also experiement with Silmic II and Cerafines.

For the film I will try Mundorf MKP, Sonicap and Audyn cap.

With these I will be able to determine subjective individual effects so everyone can "cook" the pretended result.

Hi Felipe..... I had some difficulties implementing V12 because the distance between Film output cap and the Mosfet is critical but This one is as stable as V1 and perfectly noiseless... And the gains in detail relative to V1 are substantial.


Hi Ricardo, if you can afford 1uF 400VDC try Sonicap teflons or parallel two 0.47uF FT-3 russian teflons, for 10uF my first choice is MKP non inductive Auricap

An externally hosted image should be here but it was not working when we last tested it.


An externally hosted image should be here but it was not working when we last tested it.
 
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Both are necessary: design & materials to reach our Nirvana but I agree with you: I prefer good design over good materials, always when you have a good design can upgrade to good materials:D

I supposed that you cryogenized the tape & used a special polymer used by NASA....I never suspected that you used a special gas....
 
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Hi Ricardo, if you can afford 1uF 400VDC try Sonicap teflons or parallel two 0.47uF FT-3 russian teflons, for 10uF my first choice is MKP non inductive Auricap

An externally hosted image should be here but it was not working when we last tested it.

Where did you get the Sonicap ?

The white "normal" sonicap sound better than also white "normal" Mundorf MKP.
 
the problem is that the resistor ladder fixes the emitter of Q9 @ ~24V.
The supply rising to 80Vdc, when mains is high, puts a high Vce across Q9.
I do not think he realises that.
Changing the ratios of the resistor ladder could help alleviate that problem, or simply looking at the range of worst case supply voltages that one expects the circuit to survive with.
 
By stating he put BC546 there (Vceo=65V), he must have had it in mind?

Hi Salas and Andrew,

Thanks for your help and thoughts. I turned the Vout up to 60, it took a while ( 10 minutes or so) for the Vout to stop climbing up. I adjusted it back down to 60 several times. Measured temp at Q1 at about 50 deg C and the second mosfet at almost 60 deg C. My heat sink was definately warm and is probably too small.

The LED glowed normally. I will hook the shunt up to the scope tonight and see if its oscillating.

Yes, I was concerned that I would exceed the Vceo of Q9 hence the BC546.

Ken
 
the cascode (q9) will remove much of the temperature variation in the CCS due to mains voltage changes.
The drift you have found must then be in the Shunt stage or the series FET.
Big sinks will have a profound effect on reducing temperature drift with mains variation.
Further "warm up" drift will tend to zero since the CCS passes by definition constant current.
 
I went back into the simulation and looked at some of the heat dissipation issues and realized that I have been underestimating just how hot this thing will get. So, several of my concerns were unfounded. For example at this voltage with 100ma load and 200ma current, the shunt mosfet makes over 14w of heat. And my 1k load resistor makes 3.6w of heat. I'm going to take it back to 130ma of current by changing the 3.3 ohm to 5 ohm and see if that doesn't solve some of voltage rise issues.

Ken
 
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The V1.2R example schematics

Phew, lots of drawing.
 

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