3 terminal Jung Super Regulator Kit

[fdegrove]

Hi,

I buy issues from the news-stand a couple times each year when I am traveling.

Maybe you should travel more often?

Then there's articles like the moving coil transformer project which entails putting a transformer in a plastic case with RCA jacks (not even balanced inputs for god's sake!).

Then there's people's intelligence being able to sift the crap from the nuggets?

Come on S there's only one bible and that must be your own, right?

Cheers,

[randytsuch]

Free advertising
http://www.audiocominternational.com...regulators.asp
if you want to see the regulators Fred was referring to.
They also make a q power regulator that is even more expensive.

And I for one would be interested in a reasonably priced PWB or kit.

Randy

[dipchip]

"Uh oh........ not even experts this time"

Ouch that hurt!

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"The real benefit comes from the bootstrapping the op-amp."
Well................
This is really only true at frequencies where the PSRR of the op amp is high. As the PSRR drops with increasing frequency some issues arise.


Yes, thank goodness the PSSR of the op-amp is so high in the audio range that
we are interested in.


---------------------------------------------------------------------------------
"Here lies the paradox. The whole point of a very low impedance supply is to keep the voltage at the supply pins free from modulation. In this regulator the op amp supply is intimately coupled to the op amps (via two followers) output currents modulation of its own supply."


Its not a paradox, its a benefit. Whats better. The ripple before the regulator's pass stage
or after. The inherent PSRR of the op-amp insures that the ripple after the pass stage will be less than before. The op-amps inputs
are also filtered insuring that the op-amp is not producing any oscillations, thereby not directly contributing self induced modulation.

-------------------------------------------------------------------------------
"An additional RC filter for the op amp in the regulator seems prudent to me. "

There is a RC filter already in the feedback return path.
But if a lowpass filter was added to the op-amps supply.
The R in series with the op-amps supply lines would limit slew rate
and probably decrease performance.

-Craig Beiferman (non-expert)

P.S. Fred I'm a dog person.

[janneman]

Originally posted by peranders

I think the Jung design is pretty much normal engineering science, no tweaking at all. There are better references for instance.

Also the pcb layout, normal Kirchoffs laws, and normal science, no voodoo like at >GHz.

Of course it is normal engineering, not voodoo. The trick is to get it all together in the optimum way. Surprisingly, the people that can do that seem to be just a very small proportion of those who know kirchoff and ohms law, even a very small proportion of all those with engineering degrees.

Could you give us the better references?

Jan Didden

[Elso Kwak]

Originally posted by janneman


Of course it is normal engineering, not voodoo. The trick is to get it all together in the optimum way. Surprisingly, the people that can do that seem to be just a very small proportion of those who know kirchoff and ohms law, even a very small proportion of all those with engineering degrees.

Could you give us the better references?

Jan Didden

Hi Jan,
It surprises me Per Anders is suggesting better references while he is using the LM431 is his "Ultra Low Noise Power Suppy" QSXPS.
"Better" i.e. lower noise references would be f.a. AD586, LT1021-5, Ref02, MAX6250. Signigficantly lower noise are only the AD586 and the MAX6250 with 1µF noise reduction cap applied.
I have experimented a bit with these references compared to the LM329 fed by a constant current source comprised of a red LED and a transistor. The difference in SOUND is very small I concluded, except for the MAX6250 that seems to impose its own sonic footprint on the sound. Very weird.
As Fred remarked in a earlier discussion about these type of regulators the LM329 is easier to apply.
(You can not flipover these IC type references like the LM329 for the negative supply). But a way around is the approach by Kevin Gilmore using the negative regulator as a 1x inverting amplifier of the positive regulated supply. Is that a good thing to do?

[fmak]

[QUOTE]Originally posted by Fred Dieckmann
[B]"Its only 1.75" wide by 1.5" tall. I don't think thats very big.
I blew up the layout for readability.

-----------------------------------

Wow someone spent a bomb on those BGNs.

What is the rationale for using BGNs and not the lower tan delta FKs or SG OSCONs in the digital section? The OSCONs are much smaller and by selection one can find batches that are an order of magnitude better than the BGNs. I understand SOUND was the criteria.

Also in the resistors used in the same mod by Audiocom, two chip Vishays have been selected for sonics. I would prefer the single chip S102Ks. The former are of course, even more expensive than the single chip one.

Retailing expertise??

[peranders]

Originally posted by Elso Kwak
Hi Jan,
It surprises me Per Anders is suggesting better references while he is using the LM431 is his "Ultra Low Noise Power Suppy" QSXPS.
"Better" i.e. lower noise references would be f.a. AD586, LT1021-5, Ref02, MAX6250. Signigficantly lower noise are only the AD586 and the MAX6250 with 1µF noise reduction cap applied.
I have experimented a bit with these references compared to the LM329 fed by a constant current source comprised of a red LED and a transistor. The difference in SOUND is very small I concluded, except for the MAX6250 that seems to impose its own sonic footprint on the sound. Very weird.
As Fred remarked in a earlier discussion about these type of regulators the LM329 is easier to apply.
(You can not flipover these IC type references like the LM329 for the negative supply). But a way around is the approach by Kevin Gilmore using the negative regulator as a 1x inverting amplifier of the positive regulated supply. Is that a good thing to do?

I think it's important to have low noise voltage references if you can't use heavy filtering (DAC's, ADC's). In audio it's cool to use a really expensive voltage reference but my design goal was to use normal parts, easy to get and I think 431 is a really good reference for the cost. In my case I have used a second order LP-filter and if you compare Jung's text you see that a LP-filter does wonders when we talk noise.

[janneman]

Elso, Per,

First of all I don't like to use an inverted version of a pos supply for a neg supply. What you are doing is copying noise and ripple from one supply to the other. Especially ripple, which is correlated to the signal, should be kept out as much as possible. I admit that this is not based on exhaustive testing, just my gut feeling.

I have to disagree with Per. In isolation, you CAN say that the filter does wonders. But don't forget that the end result is the outcome of a lot of related factors. Surely you agree that using both a low noise reference AND the noise filter give a better result than a mediocre reference and a filter? The same goes for the opamp. I think I read you still use the LM324 Per, really, you're doing yourself a big disserve. This opamp can't come close to a modern wideband one in terms of wideband ripple and input noise rejection, wideband very low output impedance etc. And please, don't tell me "but it sounds better". This is an engineering discussion.

Jan Didden

[peranders]

Originally posted by janneman
I think I read you still use the LM324 Per, really, you're doing yourself a big disserve. This opamp can't come close to a modern wideband one in terms of wideband ripple and input noise rejection, wideband very low output impedance etc. And please, don't tell me "but it sounds better". This is an engineering discussion.

My design idea was to use a slow opamp and creating a slow regulator because it was intended for rather constant loads. Noise isn't a big thing when opamps are used as ampiflying elements but if we talk MC, MM phono amp with discrete design it more important, very much more.

LM324 isn't so bad if they are used right but of course you can choose other types. I don't disagree on that.

16 uV noise isn't so bad (if you compare to a 78xx) but this noise is mostly generated by LM324 so it's easy to lowering the noise simply to change opamp.

[peranders]

I'm pretty amazed by this discussion compared to this .
78xx is quite alright as long as the right brand is chosen and here is 431 a peice of junk. I'm really .

If you have no demands of speed I think regulator choice is rather unimportant as long as you can filter out noise and the load is rather constant och the application doesn't need extra stable voltage.