Good supply for preamp, Comments?

[fdegrove]

Hi,

I am fine with your inability to explain. and I don't expect you to be able to do that anyway.

Unable to explain? I explained this already anyway.

Maybe people shouldn't expect others to be able to read anymore either?

Buena notte a te bambino,😉

 

[SY]

Frank, I've read data sheets, I've read the app notes, I've read Bob Pease and Erroll Dietz's stuff, and I've built quite a few units using 117-family regulators. And I'm still mystified about what you're trying to get at.

 

[Algar_emi]

Jung Reg

Thanks for your comments everyones. Following some of your advices I found very intersting reading on the Jung Super Reg and the proper connections for the LM 317 (Kelvin Sensing), Thanks ALW.

Following Peter advice I will probably build two or three different supplies and compare their sounds, if difference there is.

First I need to build the Preamp channel to figure out its real power consumption, then we will see..

Thanks again everyones.

Bye.

 

[Peter Daniel]

Re: Jung Reg

Following Peter advice I will probably build two or three different supplies and compare their sounds, if difference there is.

I would be quite interested in your findings, as I'm looking for a good preamp supply as well. Did you consider batteries?

 

[millwood]

Frank, I've read data sheets, I've read the app notes, I've read Bob Pease and Erroll Dietz's stuff, and I've built quite a few units using 117-family regulators. And I'm still mystified about what you're trying to get at.

I think I kind of see his point. But the fact that he didn't point out the usefulness of paralleling multiple caps in this design makes me believe that he is really not there.

Well, I am not going to kill brain cells trying to figure out what he knows or doesn't know.

 

[tbla]

first, read this......

http://128.121.162.80/other/LDOBk.pdf

and then built the superregs from jung/alw(and didden - allmost forgot)......as many as possible $$$

good luck...!

🙂

 

[fdegrove]

Hi,

I think I kind of see his point. But the fact that he didn't point out the usefulness of paralleling multiple caps in this design makes me believe that he is really not there.

If you care to take a look at AN-1148 page 6 and following pages regarding ESR and its influence on the performance of the regulator.

AN-1148

Cheers, 😉

 

[analog_sa]

I see i missed a lot of fun here. What i never realised was that the PS was also cloned from a Classe PS. Is this right? I'll have less trouble with the output caps if the 4700uF and 180uF are interchanged; the choke will then keep the 317 happy.

cheers
peter

 

[millwood]

first, read this......

http://128.121.162.80/other/LDOBk.pdf

and then built the superregs from jung/alw(and didden - allmost forgot)......as many as possible $$$

good luck...!

🙂

Hi,



If you care to take a look at AN-1148 page 6 and following pages regarding ESR and its influence on the performance of the regulator.

AN-1148

Cheers, 😉

I wish it hadn't taken you over 12 hours to come up with this answer. but better late than never, 🙂

So when you say everything else being equal, you didn't mean everything else, including ESR, being equal, right?

BTW, can you figure out why the original design had so many different caps in parallel? 🙂

Anyone?

 

[Algar_emi]

Battery Supply

Hi Peter. From what I red, the batteries have their own problem. According to ALW, the high internal resistance and noise seems to be the biggest. I will try the super reg. Bye...

SB

 

[Algar_emi]

Classe PS, a little correction

This supply is not from the Classe. It is rather a combination of few supplied from preamp considered to be good sounding, among them my own Simaudio preamp and I5 Amp. The parallel caps are to lower the ESR. I used the same combination that I found in my Simaudio I5 for before the regulator. My own Bryston .4B little preamp is using the LM317/337 and sounds quite good with my Aleph30 amplifier.

I got the little chokes from an audio equipment that I disassembled. I was curious to try these hearing so many good comments from the choke supply used in the Musical Fidelity gear.

I planned to used this supply to try not just the Classe clone but also 2-3 other preamp desings and compare the sound. But don't get to excited just yet. I will take me propably a year to go the full circle of my little experimentation. I'm not as fast as Peter 😎

I bying most of the parts right now. Bye...

 

[millwood]

Re: Classe PS, a little correction

This supply is not from the Classe. It is rather a combination of few supplied from preamp considered to be good sounding, among them my own Simaudio preamp and I5 Amp. The parallel caps are to lower the ESR. I used the same combination that I found in my Simaudio I5 for before the regulator. My own Bryston .4B little preamp is using the LM317/337 and sounds quite good with my Aleph30 amplifier.

I am just curious about how they sound. Do they sound positively grey and dynamically challenged?

Yeah. you can lower ESR by paralleling them. But there is more to that when you parallel different caps.

I got the little chokes from an audio equipment that I disassembled. I was curious to try these hearing so many good comments from the choke supply used in the Musical Fidelity gear.

resistors do similar things than chokes in this application. Actually when I first started in electronics, all PS, regulated or unregulated, had little chokes straddling large caps to smooth out ripples. It makes a lot of sense since current through a choke cannot change suddenly. Over the years, cost cutting forced people to replace those chokes with resistors and then completely got away with the resistors at all.

 

[jan.didden]

I wish it hadn't taken you over 12 hours to come up with this answer. but better late than never, 🙂

So when you say everything else being equal, you didn't mean everything else, including ESR, being equal, right?

BTW, can you figure out why the original design had so many different caps in parallel? 🙂

Anyone?

...to impress DIY-ers and customers?

Jan Didden

 

[fdegrove]

SLEEPLESS IN...BELGIUM.

Hi,

I wish it hadn't taken you over 12 hours to come up with this answer. but better late than never,

Do you mind???

BTW, can you figure out why the original design had so many different caps in parallel?

Assuming they are all of the same value and technology...

For economic reasons....and yes they lower total ESR, in theory.

So when you say everything else being equal, you didn't mean everything else, including ESR, being equal, right?

The caps were the only variable, no one said anything about ESR being a constant so there you go.

Cheers,😉

P.S. I hope you slept well...

 

[ALW]

I can hardly wait for ALW to see this thread.



Fred, let them believe what they want to believe.

Anyone who wants to use their ears can tell the truth, but I nearly wet myself with Sy's statement that an RC is fine for a class A amp 🙂

Might be fine for some class A amps, but definitely not for all.

Ok then guys, your starter for ten: -

What's most important in an audio PSU?

The closest answer (judged by Fred and myself) gets a free super-reg to play with, donated by me.

Any of my existing private email correspondants need not apply 😉

Andy.

P.S. don't forget you can store significant energy in a choke, it's a bit difficult in a resistor, FWIW.

P.P.S. remember most reg's have zones of stability against ESR - be very wary adding low ESR to reg's without deliberation.

 

[UrSv]

Re: I can hardly wait for ALW to see this thread.

Fred, let them believe what they want to believe.

Anyone who wants to use their ears can tell the truth, but I nearly wet myself with Sy's statement that an RC is fine for a class A amp 🙂

Might be fine for some class A amps, but definitely not for all.

Ok then guys, starter for ten, what's most important in an audio PSU, closest answer (judged by Fred and myself) get's a free super-reg to play with, donated by me.

Any of my existing private email correspondants need not apply 😉

Andy.

How could I possibly know?

I'll still try:
Regulation and regulator stability with respect to an interference/signal induced by the load from the load end for both negative and positive interference voltages.

 

[ALW]

Another clue

None of the stuff you'll read in data sheets, application notes or any other reference work I've seen will give you the answer.

In order to understand the answer, I strongly reccomend building a simple discrete linear reg.

Nothing exotic, but it will tell you more than any amount of fiddling with 3-terminal devices ever will, as you now have control over internal operational parameters.

UrSv, not nearly specific enough 😉

Andy.

 

[millwood]

Re: Another clue

...to impress DIY-ers and customers?

Jan Didden

That could very well be reason #1, 🙂

Hi,
Assuming they are all of the same value and technology...

For economic reasons....and yes they lower total ESR, in theory.

Making your statement contingent doesn't really help, Frank. Sorry that you missed (by about a mile and half), 🙂

The caps were the only variable, no one said anything about ESR being a constant so there you go.

Cheers,😉

so if the only thing that varies is the capacitance, everything else (including ESR) should stay the same right?

Now you see how unclear your orignal question was. so before blasting others for giving your the wrong answers, you may want to look at how you present your questions first.

P.P.S. remember most reg's have zones of stability against ESR - be very wary adding low ESR to reg's without deliberation.

yeah. low ESR isn't always a good thing for regulated power supplies.

None of the stuff you'll read in data sheets, application notes or any other reference work I've seen will give you the answer.
Andy.

engineers build staff and geeks read datasheets, 🙂

 

[Peter Daniel]

Re: Another clue

Nothing exotic, but it will tell you more than any amount of fiddling with 3-terminal devices ever will, as you now have control over internal operational parameters.

UrSv, not nearly specific enough 😉

I remember from reading your posts that Kelvin point (or whatever it's called) was very critical.

 

[ALW]

No cigar here

I remember from reading your posts that Kelvin point (or whatever it's called) was very critical

That is important to getting the best performance / noise spec. from a given regulator, but is in no way remotely fundamental for audio.

Andy.