I prefer discrete j-fets with some mosfets added. That is my 'thing'. However, tubes can be very, very nice, and sometimes better than fets. Bipolar transistors always worry me, even though I designed with them for many years, almost exclusively. They always seem to have excess higher order distortion due to non-linear beta and the exponential Gm characteristic. Still, I have 100's if not 1000's of them still, looking for a home.
In case you degenerate BJTs to same Gm as JFETs, to me there is not much worry; proved by listening tests.
High order harmonics?
http://web.telecom.cz/macura/dispre2_thd.png
When perfectly matched NPN and PNP halves, we achieved 0.0003% in this simple, wideband topology, only 2nd and 3rd harmonic.
High order harmonics?
http://web.telecom.cz/macura/dispre2_thd.png
When perfectly matched NPN and PNP halves, we achieved 0.0003% in this simple, wideband topology, only 2nd and 3rd harmonic.
JC
PMA
Thanks for your replies. I guess it's ye olde story, there is more than one way to skin a cat.
I was thinking of a preamp with no gain, and a cathode follower after the vol pot always sounded good to me, yet cathode followers had gained a reputation for bad sound in some quarters. If you subjectively compare a CF stage with a no feedback anode follower stage, the distortions in the latter will make the CF sound a bit bland by comparison, I believe that is the reason.
Times change and now I have an open loop LME49600 after the pot.
PMA
Thanks for your replies. I guess it's ye olde story, there is more than one way to skin a cat.
I was thinking of a preamp with no gain, and a cathode follower after the vol pot always sounded good to me, yet cathode followers had gained a reputation for bad sound in some quarters. If you subjectively compare a CF stage with a no feedback anode follower stage, the distortions in the latter will make the CF sound a bit bland by comparison, I believe that is the reason.
Times change and now I have an open loop LME49600 after the pot.
Bonsai said:
Numbers are not important. Conceptual considerations are key here.
That I cannot put it in numbers is not key. What is key is if you can grok what I'm saying and allow yourself to muse your way to something that is useful to you. It won't work out overnight either. Numbers don't exist in the real world. They are entirely a fabrication that is connected only to the mind of man on the left side of the brain.
These two paragraphs I have written will actually cause some alienation with some of you. That is not a good thing, but there is little I can do about it. When I still pursued mathematics, I was the best in any class I was in, with regards to scores. I gave it up, as my strengths lie elsewhere- and I realized it. I had made it all the way up to college calculus (first two semesters)--and then I let it go. Now I go as far as basic calculations on a calculator..and amuse myself by finding ways to innovate without ever using any math of any kind, beyond the basics. Please refer to the two above paragraphs to see how such a thing is done.
🙂
I visualize the complex fields, at the molecular level, in 3d and in time. Time is also in the model that level.
syn08 said:
You made an assumption about John's statement, an assumption made with little tempered balance in it-with regards to your response. John had the courtesy to not respond in kind. Such repeated behaviour on your part is suggestive of internal issues.
I do not foolishly exempt myself from realizing my own such behaviors in whatever way I may exhibit them, no do I think that any one of us in human form is immune to such things-in our own particular ways. However, be that as it may, one of yours is becoming quite burdensome in this particular thread.
I don't know what the lesson is, and personally I prefer to fight insult with insult. However, I am constrained from doing this on this website.
I remember reading a short story in a college English class that always stayed with me. In this story, a big fellow was verbally attacked by someone who was very good at verbal attacks. This big fellow was not as good at returning verbal attacks, so the first fellow had an advantage. I thought that the big fellow had the perfect right to take a poke at the fellow verbally attacking him, because he was being verbally attacked without cause (bullied) and he had the advantage of physical strength, and should be able to use his advantage as well. Many in my class could not understand my position, and thought the big guy should just take the abuse.
On this forum I have found that even verbal retorts from me are considered unacceptable, and I have been 'binned' for it. It just isn't worth it, even if it creates an unfair playing field. If I want to contribute here, I have to go by the rules.
If Syn08 can now contribute something useful for all of us, let him contribute. I would just love to make a cost effective enclosure that is attractive, well shielded, and non-magnetic.
We recently developed a non 'hogged out' enclosure for a new Vendetta Phono Preamp. The machinist had to do about 50 separate operations and told us that 'hogging it out' would actually be easier and cheaper. How about that? If course it had to meet our total requirements, not just the easy ones.
I remember reading a short story in a college English class that always stayed with me. In this story, a big fellow was verbally attacked by someone who was very good at verbal attacks. This big fellow was not as good at returning verbal attacks, so the first fellow had an advantage. I thought that the big fellow had the perfect right to take a poke at the fellow verbally attacking him, because he was being verbally attacked without cause (bullied) and he had the advantage of physical strength, and should be able to use his advantage as well. Many in my class could not understand my position, and thought the big guy should just take the abuse.
On this forum I have found that even verbal retorts from me are considered unacceptable, and I have been 'binned' for it. It just isn't worth it, even if it creates an unfair playing field. If I want to contribute here, I have to go by the rules.
If Syn08 can now contribute something useful for all of us, let him contribute. I would just love to make a cost effective enclosure that is attractive, well shielded, and non-magnetic.
We recently developed a non 'hogged out' enclosure for a new Vendetta Phono Preamp. The machinist had to do about 50 separate operations and told us that 'hogging it out' would actually be easier and cheaper. How about that? If course it had to meet our total requirements, not just the easy ones.
The lesson was not for you. I just thought/imagined KBK was needlessly leaping to your defense. A thread with all in agreement would be dull and short lived I feel.
No wonder I didn't understand your meaning. I appreciate REAL input from others, including criticism.
john curl said:
Verbal abuse can be received on the same levels as physical abuse. Internalizing such impact(s) can feed the same neurological response and yield similar defense(s). We all have boundaries. If it is competitive in a physical sport there could be life saving limitations. If it is competitive in “debate” there could be easily no boundaries.
If the boxer is weak, he(she) needs to practice to enhance their capability.
If the debater is lacking in written or verbal skills, they need more practice.
Not all of us are great fighters and/or debaters.
Your post disturbs me to a certain degree and I wish I never read it…I have a deep regard for your work and my respect for you withstands however somewhat modified.
Try to stick to the electronics man, there I see your thoughts are certain and your words are so strong. These other comparisons and metaphors will drag you straight to %$#@*.
So very interesting what becomes of the discussion after
a thread "matures" (same with krell and DX threads).
It turns into a shooting match over esoteric materials and
personal preferences . Interesting reading, to gauge the demeanor of the participants, but after reading the first
20 pages,where's the schematic???
OS
a thread "matures" (same with krell and DX threads).
It turns into a shooting match over esoteric materials and
personal preferences . Interesting reading, to gauge the demeanor of the participants, but after reading the first
20 pages,where's the schematic???
OS
If you wanted to build a CTC Blowtorch, you 'might' be able to do it as others have. There is no published schematic.
Predicted answer(from 20 pages).The clues might be on the other 405 pages..
"might" is probable...
"might" is probable...
ostripper said:
Wholly smoke! You said it "so bold" and there it is. Right out in the open in front of everyone! I've read this thread up and down sideways trying to fing the schematic and pcb's that would lead me to bliss. It is not here, no sir, these things are not here.
Lots of esoteric conversations, that in my mind, pertain nothing to DIY Audio, because I see no information to bring me there. YET the discussions are colorful and great to read...then this thread becomes a lunch bag let down.
Don't get me wrong! I love it all. Great stuff. But really, where is the beef and if the beef is not here then why DIY? I want the schematic, I want to try it out, I want to compare it. Else, it belongs in the DIY tease thread; where you can check it out and then later buy it in the store.
One more time here; I tip my hat that such designers are present and sharing their thoughts but in the end chaps like Nelson Pass come off looking like heros when you compare.
Perhaps it is time for me to move over to Pass Diy and live it up?
mosfets said:
If you open the line stage piccy in PP and clean it up you'll have no problem to read the value colors off the Resista MK3's, including the ones of the two regulator devices.
There have been plenty schematic guestimates posted, just leaves you to pick a number for the dark side Holco's alongside Mr C's fav. RelCap and for the erection between the dual J's.
Shouldn't be that hard for someone competent.
Attachments
1. Shielding: I never said I could do it better. How could I say such, if the target shielding performances are undefined?
2. But, relatively speaking, any competent engineer could get the same results at probably 10% the cost and effort. Which of course will kill one of the essences of the CTC: to be outrageously expensive.
3. For all yearning for the CTC schematics, PCB's, details. If the miracle would happen, you would certainly be dissapointed.
- Schematics wise, there is pretty much nothing original or different compared to other old JC preamps already belonging to the public domain. Which are mostly obsolete and of historical interest, good for a technology museum "Audio In The 20th Century".
- Good quality components (for that time), a good layout (but nothing that is not already known and followed even by competent DIYers), that's all it is about. Silver wiring, etc... is only a matter of designers fooling themselves and the naive customers.
- Don't fool yourself: the reason why the CTC is and will remain a "secret" is simply because it has to stay as a myth/legend. Protecting the brand is almost always more important than protecting the design/recipe/etc... Anybody involved in marketing knows how important is to create "legends" around a product, a line of products or a name. Let me put it in a more blunt way: engineering is expendable, marketing is not.
4. Sorry, I know how it feels. I was pissed off royally at 5 when I was told Santa doesn't exist.
2. But, relatively speaking, any competent engineer could get the same results at probably 10% the cost and effort. Which of course will kill one of the essences of the CTC: to be outrageously expensive.
3. For all yearning for the CTC schematics, PCB's, details. If the miracle would happen, you would certainly be dissapointed.
- Schematics wise, there is pretty much nothing original or different compared to other old JC preamps already belonging to the public domain. Which are mostly obsolete and of historical interest, good for a technology museum "Audio In The 20th Century".
- Good quality components (for that time), a good layout (but nothing that is not already known and followed even by competent DIYers), that's all it is about. Silver wiring, etc... is only a matter of designers fooling themselves and the naive customers.
- Don't fool yourself: the reason why the CTC is and will remain a "secret" is simply because it has to stay as a myth/legend. Protecting the brand is almost always more important than protecting the design/recipe/etc... Anybody involved in marketing knows how important is to create "legends" around a product, a line of products or a name. Let me put it in a more blunt way: engineering is expendable, marketing is not.
4. Sorry, I know how it feels. I was pissed off royally at 5 when I was told Santa doesn't exist.
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