Simplistic MosFET HV Shunt Regs

Pretty cool!
If i see this right, you have made a CLC with Mundorf Tube-Caps (47µ & ??) before the regulator for each channel, right?

Right, 4XSF4007 --> 47μF --> LL1638 (dual serial connection) --> 2X100μF
All are M-Tcaps.

Now i changed to thicker wires and re-orientated parts to further reduce cable lengths.
Of course for another time is sounds different.
After some listening and evaluation, i will terminate grounds not near the reg, but near the audio board.
 

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Right, 4XSF4007 --> 47μF --> LL1638 (dual serial connection) --> 2X100μF
All are M-Tcaps.

Now i changed to thicker wires and re-orientated parts to further reduce cable lengths.
Of course for another time is sounds different.
After some listening and evaluation, i will terminate grounds not near the reg, but near the audio board.

Hi! No noise and no hum?? How many mA do you use? what tube??
thank
 
quanghao,

no audible noise and hum anyway, even without regulators. I am using Salas regs for their influence on the sound.
Here is the schematic of my pre. Changed output tubes to PCC88, 47μF electros to film, reduced output caps to 15μF and removed 300Ω output resistor.


dvb-projekt,

are you asking me, because i cannot understand the question.
 

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quanghao,

no audible noise and hum anyway, even without regulators. I am using Salas regs for their influence on the sound.
Here is the schematic of my pre. Changed output tubes to PCC88, 47μF electros to film, reduced output caps to 15μF and removed 300Ω output resistor.


Yes! Salas shunt is very exelent! no hum no noise, the sound is very very well!
I like it!
In your cricuit, I dont like R in and r out!

Best regarder!
 
diyAudio Chief Moderator
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Now i changed to thicker wires and re-orientated parts to further reduce cable lengths.
Of course for another time is sounds different.
After some listening and evaluation, i will terminate grounds not near the reg, but near the audio board.

Since you can listen to the cable length difference you may experiment with remote sensing at a point. I.e. using 4 output wires. There are opportunities for oscillation regarding those as well, must twist or use shielded coax for the sensing pair (the pair that closes circuit for the Vref and drive). The cool part is that allows longer wiring without feeling the load nodes moving away. Drops the output wiring influences to a significant extent. Here is an example of wiring like that.
 

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I mean the R-Core transformer. Or is it a double C with air gap?

This is the original chineese R-core i was using with the tube power supply. I now using this just for the 7V filament of PCC88.

Thank you for the remote sense circuit.
I can understand that the remote sense pair will be the one near 2SK170 and MJE350, right?
I think that i have to rebuild the whole reg, because maybe it will be more difficult to modify Disco's board to do this.
 
diyAudio Chief Moderator
Joined 2002
Paid Member
Thank you for the remote sense circuit.
I can understand that the remote sense pair will be the one near 2SK170 and MJE350, right?

Right. The main pair should remain as thick as originally for 2 wires. The sense pair is good to be as thick too, but if just twisted presents some oscillation (can see with a scope, or be aware of subjective roughness showing up), you can try shielded coax. Remote sensing works generally, now I can't be sure for your build, but it is worthy to try out. Don't forget that without the 4 wires meeting at their load ends, the circuit isn't complete for testing.