An interesting first comment by the man him selv.john curl said:
I am not familiar with these levels refered to.
It is probably because of my unluck to been born european in a non-angelican cold country close to Ice-Land.
Dividing people into levels and categorys werent never my strong side.
It is quite enough for LINEUP to classify amplifiers into Class A, AB, B.
And to keep track on his bloodgroup, in ccase anything happens.
( I have blood type B )
I could instead quote The Man Him Self (Robert Marley of Jamaica .. if you didnt already know)
.. even if he is buried and dead,
just like John 'Give Peace A Chance' and Mr. Luther 'I have A Dream today':
Got to come together
We are birds of a feather;
We got to come together
'Cause we are birds of a feather;
Got to come together
'Cause we are birds of a feather;
Or there will never be (Lord, have mercy!)
no love at all -
There will never be - yeah, yeah! -
no love at all.
We also got to realize we are one people, yeah!
Got to realize that we are one people, yeah!
We got to realize we are one people,
Or there will never be no love at all -
There will never, never, never be no love at all.
Got to build our love on one foundation;
Got to build our love on one foundation;
Got to build our love on one foundation;
Got to build our love on one foundation;
Got to build our love on one foundation ... /fadeout/
Now the noise in JFETs and John ideas
are always subjects that will intrigue people here.
This does not necessarily mean we ever can reach a final TRUTH in these matters.
I would say most probablely not
But there is good value in our social interaction while we debate and explore.
Makes us feel a bit less alone .. for an hour or two.
After all, even if we are not BIRDS of a feather,
we are all born as being SOCIAL Creatures.
Like other pigs, cows or hens or other kinds of Apes (Monkees).
/lineup
Lineup, I am 10 years older than you, AND I seem to have a lot of experience with certain things. One, is the acceptance of new ideas, especially in electronics. I have stated the 3 levels, repeatedly, and you can find a version of them in 'Murphy's Laws', a long known repository of common wisdom.
Who put so many transistors in my guitar overdrive effect? 
An externally hosted image should be here but it was not working when we last tested it.
Thanks, Homemodder!
I have asked www.sh-halbleiter.de and Kessler if they have 500 pcs of each.
Best,
Sigurd
I have asked www.sh-halbleiter.de and Kessler if they have 500 pcs of each.
Best,
Sigurd
homemodder said:
There is one thing that consistantly gets worse,john curl said:
this is the physical state of one brain.
True, but 10 years or so it can be compensated for with your stored experiences.
Depends on how well or not you cared for your head with drinking eating poisoi'ns and accidents, boxing , carc-rashes , too.
I understand you do not want to repeat yourself just for an elderly 'swede' in the far north-east.
The day of today belongs to them young, doesnt it?
But at least you could, Johnny, make an exception and provide a reference link.
About the 5 levels, of which you probably is to be considered to be at stage 4. Ahead of us all, for sure
Thanks.
Now, I do not even know how these levels are defined.
Can it be amplifier knowledge in general.
Or more narrowed down to a small group of transistors called Junction Field emitter devices?
Give one refreence or at least point me somewhere, please.
And I will owe you one, if you do.
Hmmm. Maybe some other more kind and less in need of gettin' to feel less lonely for an hour or so,
with a younger and more quickly repsonsive mind cell structure
could
help me ol'/lineup - sorry to be such bother - but it might be what my disfunctional brain got me into this instance
.... God, if they could express themselves as bright in Swedish
as I do in the foreign lang. of British English (started learn this at age=9)
Here some 3 circuits to compare.
They all have different merits,
but not necessarily, the one of performing beneeth the general noisefloor found in electromagnetic fields of typical Western Hemisphere livingrooms.
There is different noise levels far in the tropical rainforrest,
no doubt. (water+trees blocks, screens radio cummnication).
LowNoise multi parallelled differential BC550 bipolar input RIAA (from old Elektor originally)
http://www.diyaudio.com/forums/showthread.php?threadid=91497
LSK389 JFET input pair to LowNoise bipolar Op-amp
http://www.diyaudio.com/forums/showthread.php?postid=1519372#post1519372
Cicuit: http://www.diyaudio.com/forums/attachment.php?s=&postid=1519372&stamp=1211672608
I guess it does not match your suggested design in 1st post,, syn08.
But my circuits can not be called as being 'bad ideas', either.
http://www.synaesthesia.ca/files/headamp.png
What do you think, John?
And what does the topic strater syn08 have for comment ..?
I just dont like to make gigantic and complicated circuits
just to hunt for lower noise than runs through the RCA-plugs teminated Cables
that feed my input.
Sometimes such efforts is both a waste of lifetimeand a Chasing all the 4 winds. For nothing gained.
/lineup
often pragmatic and practical, as well. And not intirely up into the blue. More down to Diy-Audio levels.
Lumba Ogir said:
Lumba Ogir.
Nice comment. I have a feeling you are not one school classroom boy either?
The ambiguiety of the word 'point' .. is noted.
When people make points, like John can do occationally,
and by the way you too, Lumba
.. these points can be seen as one target area, point.
Tala är silver, tiga är guld!!!
Talk is silver, keeping-it-in is gold!!! (Silence is Golden)
It is just as true in English as in Swedish.
I am sorry I am late to this good topic started by syn08
initiated in Honor to an old man ~68 ... John Curl
But I try to go back and read, in order not to misplace any out of topic posts more.
Lycksele, nästan snöfritt nu i Slutet på maj.
Almost free frpm snow now in end of May.
... only the biggest snowpackage remain .. put there by Traktor (Caterpillar) in wintertime.
lineup said:
................
LowNoise multi parallelled differential BC550 bipolar input RIAA (from old Elektor originally)
http://www.diyaudio.com/forums/showthread.php?threadid=91497
...............
Hi Lineup,
I'm impressed by the number of input trannies, but does it any good if R18=270 Ohms? (2.1nV/rtHz !!!)
Regards,
Edmond.
lineup said:
1. Totally :bs: You can parallel bipolars and JFETs until the cows come home, if the feedback resistor is 270 ohm, that's what will set the noise. 270 ohm has about 2nV/rtHz, barely good for MM. One, max two of the BC550/560 devices are already under that noise level.
2. Not good. The 5534 is wrongly wired. R1gain sets the noise, and you won't be able to make it very small with that opamp. Don't do differentials for low noise, you'll only increase the noise by SQRT(2) compared to single ended. The current sources will add common mode noise and any imbalance will put it on the output.
You'd do better with a simple opamp stage; an AD797, OPA211, LT1115, LT1128, LME49710, ADA4898 will easily do 1nV/rtHz, better than you can expect with any of the above.
BTW, this is the HPS 3.1 input stage latest schematic. http://www.synaesthesia.ca/files/front_end_new_servo.png This is a fixed gain input stage (gain is set to 40), you need to add the RIAA correction stage(s). At the end, it's pretty complex, the board has 9.4" x 4" (including the power supplies for a dual mono version).
Lineup, at least you gave it a good shot.
Ck # 1 looks like something we might have made in the early '70's, before complementary jfets. Good comp-diff design, same topology as later JC-2 output stage (1973) except the JC-2 used fets on input. Inefficient use of low noise devices due to differential, as 4 times more devices must be used than JC-1 circuit to approximate noise, even open loop.
Feedback resistor, as already shown by others, throws away everything.
Ck # 2 comes from app note from Siliconix in late '70's early '80's, and IS noisy because the noise of the second stage of the 5534 is worse than expected.
Sound good, however.
We made these as replacements for standard 5534 for Dave Wilson to use in his WAMM speaker system for years. Still have one around in a drawer, somewhere.
Ck # 1 looks like something we might have made in the early '70's, before complementary jfets. Good comp-diff design, same topology as later JC-2 output stage (1973) except the JC-2 used fets on input. Inefficient use of low noise devices due to differential, as 4 times more devices must be used than JC-1 circuit to approximate noise, even open loop.
Feedback resistor, as already shown by others, throws away everything.
Ck # 2 comes from app note from Siliconix in late '70's early '80's, and IS noisy because the noise of the second stage of the 5534 is worse than expected.
Sound good, however.
We made these as replacements for standard 5534 for Dave Wilson to use in his WAMM speaker system for years. Still have one around in a drawer, somewhere.
Lineup, I regret that I am retarded when it comes to computers. I can't easily create a link, and I can't post anything directly.
However, I can tell you the 3 laws of design: Developed from Clarke's Laws, and put into Murphy's laws over the decades.
1. It won't work.
2. It works, but it's not important.
3. We invented it.
This and its variations have been around for decades AND can be found by anyone who is energetic enough to Google:
However, I can tell you the 3 laws of design: Developed from Clarke's Laws, and put into Murphy's laws over the decades.
1. It won't work.
2. It works, but it's not important.
3. We invented it.
This and its variations have been around for decades AND can be found by anyone who is energetic enough to Google:
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