The front will not oscilate, although I haven't done phase analysis.
Crossover between the channels is not supposed to happen.
The class is AB in stupid terminology. Standard push pull in also stupid terminology. Standard common collectors in normal terminology.
The problem with push pull is nonlinearity when crossing the 0 as far as I can see. Not possible in operational amplifier controlled and feedbacked common collectors and operational amplifier.
Crossover between the channels is not supposed to happen.
The class is AB in stupid terminology. Standard push pull in also stupid terminology. Standard common collectors in normal terminology.
The problem with push pull is nonlinearity when crossing the 0 as far as I can see. Not possible in operational amplifier controlled and feedbacked common collectors and operational amplifier.
Steven, some of your ideas may be interesting, but is it just possible you could deliver them without all the pontificating?
If you wish to use alternative terms, fine, but really, to go on and on about how all these industry standard terms are "stupid" and other abolutes of judgement gets rather tiring and offputting.
If you wish to use alternative terms, fine, but really, to go on and on about how all these industry standard terms are "stupid" and other abolutes of judgement gets rather tiring and offputting.
Tere is plenty of phase margin in unity gain in TL084. The capacitive loads are not so high.
As I have mentined: Phase analysis must be done BUT for completion of design purposes. Just because they must ALWAYS be done. In this case, problem with oscillation due to high inductive loads is not suspected but must be checked as they must always be checked.
In the worst case: get rid of some of the filters.
Lowering the capcitors will not help because the cut off frequency (the RC product) is the same.
Again, the only way to find out is to calculate the phese shift and look in the spec of TL084 and see whether the natural phase shift of TL084 due to output resistance and output capacitance and the phase shifts introduced by all inductive loads throughout the circuit would not be more than 180 degrees.
Will do but not now. Not so important. Not so interesting. Just a must from a theoretic point of view.
Anyways, the phases are 1/(tan -f/20) and 1/(tan -f/25000). Calculate and look up in case you want.
As I have mentined: Phase analysis must be done BUT for completion of design purposes. Just because they must ALWAYS be done. In this case, problem with oscillation due to high inductive loads is not suspected but must be checked as they must always be checked.
In the worst case: get rid of some of the filters.
Lowering the capcitors will not help because the cut off frequency (the RC product) is the same.
Again, the only way to find out is to calculate the phese shift and look in the spec of TL084 and see whether the natural phase shift of TL084 due to output resistance and output capacitance and the phase shifts introduced by all inductive loads throughout the circuit would not be more than 180 degrees.
Will do but not now. Not so important. Not so interesting. Just a must from a theoretic point of view.
Anyways, the phases are 1/(tan -f/20) and 1/(tan -f/25000). Calculate and look up in case you want.
I don't use alternative terms but, rather, basic terms.
I know these are industry standard terms but I don't like them.
I will try to take your advice seriously and not to pontificate against but I believe the people who invented them pontificated and dictated them.
I just wanted to find more people to rebel. In sound, things are not so bad. In other fields of expertise, things are out of hand.
To be honest, I even think people have died because of terms with which military is full.
I do not want to be pathetic and I do not want to ridicule you, please do not take this post wrogly. I just want to say what I have heard: I have heard someone to use the term "Biological Unit Worker" for a cow milker. This is funny but there are other things which create so many problems and misunderstanding. Again, in electronics and sound, things are not so bad.
I promise to try the best I can to resist talking against and stop.
I know these are industry standard terms but I don't like them.
I will try to take your advice seriously and not to pontificate against but I believe the people who invented them pontificated and dictated them.
I just wanted to find more people to rebel. In sound, things are not so bad. In other fields of expertise, things are out of hand.
To be honest, I even think people have died because of terms with which military is full.
I do not want to be pathetic and I do not want to ridicule you, please do not take this post wrogly. I just want to say what I have heard: I have heard someone to use the term "Biological Unit Worker" for a cow milker. This is funny but there are other things which create so many problems and misunderstanding. Again, in electronics and sound, things are not so bad.
I promise to try the best I can to resist talking against and stop.
Also, thank you for the good words but I have not expressed any original idea. This is not the reason for the previous talk against terms. The reason was experience with other works.
I appologise to have offended you.
I appologise to have offended you.
I have appologised and will try not to.
I am not liked by anyone usually so you will not eable to read the posts. You will not miss anything, though. There is nothing new I have said. I have not invented anything.
You are right, I have taken some pleasure in talking some things BUT I have definitely NOT meant to put people offside.
I am not liked by anyone usually so you will not eable to read the posts. You will not miss anything, though. There is nothing new I have said. I have not invented anything.
You are right, I have taken some pleasure in talking some things BUT I have definitely NOT meant to put people offside.
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Care to make a small wager on that oscillation? You clearly don't know what you're talking about. Your 'non biased' "operational amplifier controlled and feedbacked common collectors and operational amplifier" will most certainly exhibit crossover quirks and will be more audible at low levels.
Time to exit this nonsense. Bye.
G²
I can't see no crossover here. There is no "crossover" between the two transistors in a single channel as well as between the channels. THIS IS WHY THEY ARE FEEDBACKED AND OPERATIONAL AMPLIFIER CONTROLLED. NO WAY TO HAVE NOTHING. The output will exactly "repeat" the "shape" of the input, just amplified. In case this was a buffer, the output would just repat (follow) the input.
THIS CIRCUIT IS THEORETICALLY PERFECT. The only problem with this circuit, as far as I can think now, may be driving capacitive loads because of the phase shift which, when becomes 180 degrees (along with the phase shift of the operational amplifier, add to this 5pF capacitance of the base emitter junction) acts as an "invertor" at the end and "inverts the voltage which is to be returned to the input of the amplifier by the feedback. When inverted, the operational amplifier will not be able to control but will oscillate, i.e. the negative feedback will become a positive feedback.
Thankfully, phase analysis is very well defined and allows for perfect calculation as well as the phase shift of the operational amplifier is very well calculated and written in the specifications.
I have not done the phase analysis but I will do so. In case you want to do it, do it. Simple and quick.
Neither you nor I can win against the feedback. The feedback make the things perfect.
Not only the output. EVERYTHING WITH THIS SCHEMATIC IS 100% STANDARD AND I HAVE NOT INVENTED ANYTHING. Just routine stuff. The only "ingenious" thing is to get 2 18V AC transformers off the shelves and connect them as shown to make 36V because there aren't 36V DC + middle point power supplies in the shops. This is all. So, may I suggest in case you want to talk nonsense, go talk to the inventors of each of the chains. In case you want to say somehting real, you are very welcome. In case you would like the "ingenious invention" of combining two transformers, then go ahead. In case you prefer to go more, we can discuss the "ingenious invention" of paralleling 3 * 12 PC power supplies to make one 36V DC power supply.
Yes. Exit the nonsense.
THIS CIRCUIT IS THEORETICALLY PERFECT. The only problem with this circuit, as far as I can think now, may be driving capacitive loads because of the phase shift which, when becomes 180 degrees (along with the phase shift of the operational amplifier, add to this 5pF capacitance of the base emitter junction) acts as an "invertor" at the end and "inverts the voltage which is to be returned to the input of the amplifier by the feedback. When inverted, the operational amplifier will not be able to control but will oscillate, i.e. the negative feedback will become a positive feedback.
Thankfully, phase analysis is very well defined and allows for perfect calculation as well as the phase shift of the operational amplifier is very well calculated and written in the specifications.
I have not done the phase analysis but I will do so. In case you want to do it, do it. Simple and quick.
Neither you nor I can win against the feedback. The feedback make the things perfect.
Not only the output. EVERYTHING WITH THIS SCHEMATIC IS 100% STANDARD AND I HAVE NOT INVENTED ANYTHING. Just routine stuff. The only "ingenious" thing is to get 2 18V AC transformers off the shelves and connect them as shown to make 36V because there aren't 36V DC + middle point power supplies in the shops. This is all. So, may I suggest in case you want to talk nonsense, go talk to the inventors of each of the chains. In case you want to say somehting real, you are very welcome. In case you would like the "ingenious invention" of combining two transformers, then go ahead. In case you prefer to go more, we can discuss the "ingenious invention" of paralleling 3 * 12 PC power supplies to make one 36V DC power supply.
Yes. Exit the nonsense.
Dear SSB,
I would suggest you read a few of the detailed design threads that have been running in the solid state section. It might give you some insights and ideas?
You could read the Curl Blowtorch thread PtI & II, it rambles a bit, but it will keep you busy for a month I would guess... a good read. Top designers / engineers participating.
There are others I can recommend, if you are interested.
You said: "The feedback make the things perfect." Unfortunately this is untrue.
You seem passionate about designing audio. That is good. You said that people don't like you usually. Well we can't see you so we can only form an opinion based on what you say. I can see enthusiasm. But I don't see that you think that others thinking and engineering ideas and experience might be superior to what you have learned thus far. Fyi, there are a LOT of people here whose level of knowledge and expertise FAR exceeds mine. I know my limitations and am careful to not overstate. I ask questions whenever I am unsure that my facts are 100% solid. I offer advice when I am reasonably certain that what I say is likely correct. IF someone says that I am incorrect, or wrong, I either look it up and/or ask for more information. When found wrong, I always acknowledge that and correct myself.
You might find that your designs and ideas - that you decided to publish here - will bring a range of comments many of which are helpful and useful. It's like a FREE engineering seminar.
Suggest that you might not take a position of superior ability or knowledge and try a more humble approach?
_-_-bear
I would suggest you read a few of the detailed design threads that have been running in the solid state section. It might give you some insights and ideas?
You could read the Curl Blowtorch thread PtI & II, it rambles a bit, but it will keep you busy for a month I would guess... a good read. Top designers / engineers participating.
There are others I can recommend, if you are interested.
You said: "The feedback make the things perfect." Unfortunately this is untrue.
You seem passionate about designing audio. That is good. You said that people don't like you usually. Well we can't see you so we can only form an opinion based on what you say. I can see enthusiasm. But I don't see that you think that others thinking and engineering ideas and experience might be superior to what you have learned thus far. Fyi, there are a LOT of people here whose level of knowledge and expertise FAR exceeds mine. I know my limitations and am careful to not overstate. I ask questions whenever I am unsure that my facts are 100% solid. I offer advice when I am reasonably certain that what I say is likely correct. IF someone says that I am incorrect, or wrong, I either look it up and/or ask for more information. When found wrong, I always acknowledge that and correct myself.
You might find that your designs and ideas - that you decided to publish here - will bring a range of comments many of which are helpful and useful. It's like a FREE engineering seminar.
Suggest that you might not take a position of superior ability or knowledge and try a more humble approach?
_-_-bear
Sorry to have left this impression. Please, read this before everything else, this will clear everything:
I DO NOT THINK I AM SUPERIOR TOWARDS PEOPLE AND DEFINITELY NOT TOWARDS ENGINEERS NOR I AM SMARTER. I DO THINK I AM SUPERIOR TOWARDS ELECTRONICS AND SO ARE YOU AS WELL AS EVERYONE ELSE. Superior is a word which I have used because of the previous message. What I mean is I think all electronics being for instrumentation, automation, power, sound or any other field is a very simple thing to do. This is one of the reasons to make a lot of mistakes mainly with simple things, mistakes of which I am annoyed of but not always. I do take the whole electronics as a joke, even less complicated than simple arithmetic. Please, understand: I do NOT talk of sound. I do talk of all electronics.
Generally, I do NOT believe I would change this opinion but I respect yours and other peoples opinion also because this field which I think is simple has a tremendous impact. I am sorry for the expression and I do NOT want to insult anyone but, to be clearer, I would say electronics and computer hardware and software are a blue collar fields. There may be exceptions but not a lot to change the rule. Some would say this and this is difficult. Yes but not the hardware nor software part of the job. Some may build a huge analogue computing system or complicated software but not the hardware and the software have been complicated. The mathematical algorithms may have been but not the implementation.
Do I have bad attitude against engineers and blue collar workers? NO! A race car driver is a blue collar worker. No one hates a race car driver.
I have a lot of friends who are engineers, some of the either do or used to do sound engineering, some of them analogue sound other digital, mainly software, some pure digital hardware sound, not even micro controller around.
The main reason for uploading things to this site was the prices around. I believed a lot of people would get an idea, change this a bit and build themselves whatever at a fraction of the prices in the shops. The quality may not be as high but the job would be done and, in most or some applications, the job would be done fairly well. Enthusiasm, interesting, jokes, fun have been other reasons.
There is some point in this, although, generally not so true. The parts are difficult to find in general purpose shops. Some very expensive. Here is an example: An aluminium enclosure costs $100 in an inexpensive shop for electronics. Even a superb design which is for free and the parts are for free would cost at least $100. When you put the power supply, I can't count so much. I always forget the speakers when the price comes to play. One can get a good amplifier second hand for the price of the enclosure of a self made one.
So, I had an idea to use whatever is available: speakers from old stuff, usually for free or a few dollars, enclosure from wherever, power supply from whatever available etcetera.
Usually, most of the stuff can be made by using off the shelf second hand stuff, for example, one can make a guitar amplifier out of a stereo.
The site is called DIY Audio and not DIY High Performance Only Audio.
Can everyone do these circuits? Yes. More: children in secondary schools can do better than I can. High school students are professors.
You've mentioned you think there are engineers who are better. I did not like this point. There are no good or better engineers. Engineering is just a basic thing. Are there people who are better than you in calculating 2+2?
As a gross generalisation ENGINEERING IS NOT SCIENCE. This is why they called this engineering. Otherwise, they were to call Electronics Engineering, Electronics Science. True, one may say engineering is physics but engineering is very low level practical part of physics in case at all part of anything. To say an electronics engineer is a scientists is like to say a car mechanic is instrumental in building the Space Shuttle.
On answers and posts: I WILL NOT DO THIS VERY OFTEN. A few days just like a child with a new toy. Then less often. Then never.
I accept all opinions. I am not stubbornly closed in own world of opinions disregarding the rest. One reason is because no one can get a coming of a given thought when this person wants. Some thoughts don't come, other thoughts come, pretty random. Whoever says this resistor is wrong or this can be done an easier way or whatever, I am happy to take this. I will never change the opinion I have on electronics as a “field of expertise”, though. When I say Electronics, I mean the application engineering not the actual making of silicon.
Do I like to ridicule the whole Electronics? Yes. Do I like to ridicule a person who does this? NO!
On the funny side: There was a guy who have spent 30 minutes to explain the principle of carburettor while another poured 200ml of water in the throttle and started the car. Don't take this wrong: nothing against the person who was explaining: very smart and good in this and any other engine and car field but just the situation is funny. Same with electronics. There are guys who will paint the whole wall in formulas whereas others just put a resistor and the job is done. The guys who paint the wall are not bad. Neither is the guy who puts a resistor. Just funny is to thing electronics is bigger than growing chicken, for example.
I DO NOT THINK I AM SUPERIOR TOWARDS PEOPLE AND DEFINITELY NOT TOWARDS ENGINEERS NOR I AM SMARTER. I DO THINK I AM SUPERIOR TOWARDS ELECTRONICS AND SO ARE YOU AS WELL AS EVERYONE ELSE. Superior is a word which I have used because of the previous message. What I mean is I think all electronics being for instrumentation, automation, power, sound or any other field is a very simple thing to do. This is one of the reasons to make a lot of mistakes mainly with simple things, mistakes of which I am annoyed of but not always. I do take the whole electronics as a joke, even less complicated than simple arithmetic. Please, understand: I do NOT talk of sound. I do talk of all electronics.
Generally, I do NOT believe I would change this opinion but I respect yours and other peoples opinion also because this field which I think is simple has a tremendous impact. I am sorry for the expression and I do NOT want to insult anyone but, to be clearer, I would say electronics and computer hardware and software are a blue collar fields. There may be exceptions but not a lot to change the rule. Some would say this and this is difficult. Yes but not the hardware nor software part of the job. Some may build a huge analogue computing system or complicated software but not the hardware and the software have been complicated. The mathematical algorithms may have been but not the implementation.
Do I have bad attitude against engineers and blue collar workers? NO! A race car driver is a blue collar worker. No one hates a race car driver.
I have a lot of friends who are engineers, some of the either do or used to do sound engineering, some of them analogue sound other digital, mainly software, some pure digital hardware sound, not even micro controller around.
The main reason for uploading things to this site was the prices around. I believed a lot of people would get an idea, change this a bit and build themselves whatever at a fraction of the prices in the shops. The quality may not be as high but the job would be done and, in most or some applications, the job would be done fairly well. Enthusiasm, interesting, jokes, fun have been other reasons.
There is some point in this, although, generally not so true. The parts are difficult to find in general purpose shops. Some very expensive. Here is an example: An aluminium enclosure costs $100 in an inexpensive shop for electronics. Even a superb design which is for free and the parts are for free would cost at least $100. When you put the power supply, I can't count so much. I always forget the speakers when the price comes to play. One can get a good amplifier second hand for the price of the enclosure of a self made one.
So, I had an idea to use whatever is available: speakers from old stuff, usually for free or a few dollars, enclosure from wherever, power supply from whatever available etcetera.
Usually, most of the stuff can be made by using off the shelf second hand stuff, for example, one can make a guitar amplifier out of a stereo.
The site is called DIY Audio and not DIY High Performance Only Audio.
Can everyone do these circuits? Yes. More: children in secondary schools can do better than I can. High school students are professors.
You've mentioned you think there are engineers who are better. I did not like this point. There are no good or better engineers. Engineering is just a basic thing. Are there people who are better than you in calculating 2+2?
As a gross generalisation ENGINEERING IS NOT SCIENCE. This is why they called this engineering. Otherwise, they were to call Electronics Engineering, Electronics Science. True, one may say engineering is physics but engineering is very low level practical part of physics in case at all part of anything. To say an electronics engineer is a scientists is like to say a car mechanic is instrumental in building the Space Shuttle.
On answers and posts: I WILL NOT DO THIS VERY OFTEN. A few days just like a child with a new toy. Then less often. Then never.
I accept all opinions. I am not stubbornly closed in own world of opinions disregarding the rest. One reason is because no one can get a coming of a given thought when this person wants. Some thoughts don't come, other thoughts come, pretty random. Whoever says this resistor is wrong or this can be done an easier way or whatever, I am happy to take this. I will never change the opinion I have on electronics as a “field of expertise”, though. When I say Electronics, I mean the application engineering not the actual making of silicon.
Do I like to ridicule the whole Electronics? Yes. Do I like to ridicule a person who does this? NO!
On the funny side: There was a guy who have spent 30 minutes to explain the principle of carburettor while another poured 200ml of water in the throttle and started the car. Don't take this wrong: nothing against the person who was explaining: very smart and good in this and any other engine and car field but just the situation is funny. Same with electronics. There are guys who will paint the whole wall in formulas whereas others just put a resistor and the job is done. The guys who paint the wall are not bad. Neither is the guy who puts a resistor. Just funny is to thing electronics is bigger than growing chicken, for example.
SSB,
You are not "listening".
If you are reading what I wrote, then you are missing key ideas and concepts.
Perhaps English is not your native language?
Again, you should look around. Why? Because you have made assumptions and stated presumptions that are incorrect factually. Both about the nature of "engineering" (I also said designers) and the scope of this forum.
In terms of the scope of this forum things range from very very simple to virtually leading edge state of the art. You should read more and look around.
I am trying to be polite to you so that you can in essence help yourself.
By way of an example of how you are missing some things - there have been multiple discussions on the effects of different types of feedback, global loop feedback vs. nested loop feedback, distortion canceling circuits, TIM and other similar ideas. With circuits, with designs, with examples of circuits that have been built, etc...
When you say this: "You've mentioned you think there are engineers who are better. I did not like this point. There are no good or better engineers. Engineering is just a basic thing. Are there people who are better than you in calculating 2+2?"
I think you did not understand what I meant.
The idea is that you can learn from people here.
The other idea is that engineering is not basic, it requires deeper understandings except on the most rudimentary levels. When it comes to making sound, engineering is merely a tool, the artists palette.
If you want inexpensive stuff, you can by a 70w x 2 digital amp right now all done and working in a box for way under $100USD. Similarly you can buy all sorts of low cost kits and parts and even finished on ebay for low $$...
I personally understand not having a budget and having to scrounge parts. Nothing wrong with that...
Slow down, relax and take a deep breath?
_-_-bear
You are not "listening".
If you are reading what I wrote, then you are missing key ideas and concepts.
Perhaps English is not your native language?
Again, you should look around. Why? Because you have made assumptions and stated presumptions that are incorrect factually. Both about the nature of "engineering" (I also said designers) and the scope of this forum.
In terms of the scope of this forum things range from very very simple to virtually leading edge state of the art. You should read more and look around.
I am trying to be polite to you so that you can in essence help yourself.
By way of an example of how you are missing some things - there have been multiple discussions on the effects of different types of feedback, global loop feedback vs. nested loop feedback, distortion canceling circuits, TIM and other similar ideas. With circuits, with designs, with examples of circuits that have been built, etc...
When you say this: "You've mentioned you think there are engineers who are better. I did not like this point. There are no good or better engineers. Engineering is just a basic thing. Are there people who are better than you in calculating 2+2?"
I think you did not understand what I meant.
The idea is that you can learn from people here.
The other idea is that engineering is not basic, it requires deeper understandings except on the most rudimentary levels. When it comes to making sound, engineering is merely a tool, the artists palette.
If you want inexpensive stuff, you can by a 70w x 2 digital amp right now all done and working in a box for way under $100USD. Similarly you can buy all sorts of low cost kits and parts and even finished on ebay for low $$...
I personally understand not having a budget and having to scrounge parts. Nothing wrong with that...
Slow down, relax and take a deep breath?
_-_-bear
I do listen very well but we seem to have miscommunication which is not based on languages.
If you or anyone else believe the assumptions and presumptions, as you call them, are incorrect you can just post this and the problem will be solved. You can pinpoint what or just say in general. Whoever reads will not trust a given person but read everything, check everything and then decide.
I have NEVER been impolite in this forum but you may have left with a wrong impression.
I do NOT want to make a lot of effort to explain everything. ANY STABILISING, NEGATIVE FEEDBACK MAKES THINGS PERFECT. This is a very basic and true statement. The things must be designed to be stablised, though, not to have been designed to generate or oscillate. HOW PERFECT IS A GIVEN FEEDBACK IS ANOTHER QUESTION. You may play words with the word "PERFECT", there is no more perfect than perfect and there is no less, etcetera. The meaning is very clear, I hope, though.
Everyone needs help. Thank you for the good intention. Reading this forum is not the only thing I want to do but, yest, the more one reads the better. Even when something is simple and basic and well known. Better to be read even more. Again: I can always get a book or download online or read the forum. I do not want to do this ONLY, though.
Mistakes happen as I have mentioned and will continue to happen. The feedback is perfect is not a mistake but, I believe, misunderstanding of what one means. I can try to express this again with other words: A feedback is perfect means a feedback, when intended to stablise, perfectises the circuit as compared with the same circuit without the feedback. Obviously, there are different levels of feedback or different percentage with 100% feedback being what is what you have in a buffer. This statement for the perfect feedback is true NOT ONLY IN CASE OF SOUND OR ELECTRONICS BUT EVERYWHERE IN TECHNOLOGY OR WHEREVER A FEEDBACK CAN BE APPLIED, GENERALLY SPEAKING. The specific way you do the feedback: whether current, voltage or the toilet tank is irrelevant. Feedback is separate from the application. The science of the feedback is not electronics nor sound engineering but Automation. You may call Automation science rather than engineering also because Automation deals with feedbacks NOT ONLY in amplifiers or electronics but EVERYWHERE. Do NOT be insulted but sound is a place where feedback is used the least.
I have spent 15 minutes for typing this message. Also I have never wanted to type this or part of this message. If you really want to be polite, please, try to ask others what one may mean by saying so. There is nothing wrong if I hadn't explained this or you didn't understand. No one can understand everyone and no one can explain everything to anyone perfectly. This is why I have made a very clear point on terminology. Must not be used but, when necessary, use as tiny as possible.
If your point has been to read in order to find out I am wrong to think electronics is as simple as 2 + 2, though, this will be an insult. First I have seen enough, second even if I haven't, ONE DOES NOT NEED TO SEE A GIVEN THING IN ORDER TO UNDERSTAND WHAT THIS THING IS. This is why one can think. So, even if one hasn't seen electronics, one can analyse what thinking is necessary to be applied by a given person in order to achieve something. THIS IS CALLED PSYCHOLOGY and not electronics nor psychiatry. PSYCHOLOGY, SO THEY SAY, IS A SCIENCE OF HOW PEOPLE THINK. Please, ask a friend what I mean and do NOT be insulted, I do not mean what you may think. All I mean is for you or anyone else to ask a PSYCHOLOGIST what is involved in electronics by talking to this person of how electronics problems are solved and circuit designed. The psychologist doesn't need to know anything of electronics or sound. The psychologist will evaluate what kind and how much thought is necessary for electronics design. I do NOT want to spend more to communicate this to you.
I am 100% sure, a psychologist would tell you electronics is always very basic and primitive thinking at any level and, more, there aren't different levels of electronics, everything is 2 + 2 = ? There are different levels of mathematics but not different levels of electronics.
Of course, you may decide to enter a discussion what electronics means at this point but I do NOT want to. I have mentioned electronics is different than the mathematics and other "tools" used with electronics. Please, talk to a friend on this subject. DO NOT TAKE THIS WRONG: I don't mean to say you do not know electronics, I mean to say you do but to know electronics doesn't necessarily mean to know what electronics is. From talking to many people, I may say I am sure the best in the field, as you say, do not. This does not make them less best. Just one thing does not have anything to do with another. To know what electronics is and how electronics differs from the other sciences used therewith is a subject of field classification. This subject is not carried out by specialists in electronics. Not to sound bad, I will also continue to talk with various people what electronics is and what is subject of electronics and what is subject to other fields and sciences which may be used with electronics. To know all of this fields doesn't mean to be able to classify them on the contrary may mean inability to do so.
Also, I have spoken to psychologists on thinking, problem solving, etcetera. I say this just to know I do not play superior by saying this. You may also have. I don't know. If you have, then may I suggest we leave this topic to the psychologists with different opinions to decide and accept we cannot solve this problem.
The point I clearly disagree with you has been mentioned previously, but I will say this again: ENGINEERING IS ALWAYS BASIC. There aren't different levels. Again, we can leave this to be decided by people who are supposed to do this and we are definitely not these people. In case you are one of them, I am still not. But I have spoken to many who also are. I have already mentioned: this is a subject for people who deal with thinking, etcetera.
The budget is not an issue. The issue is the price. Even if I had all the money in the world, I would still look for a better price solution. Whether I will use such or not is another story.
I am able to purchase a good quality analogue amplifier from the 70's for less than $5, for example.
I have spent more than 1/2 hour for this message which I have not wanted to type. SOME of the messages I type, I may WANT to type. Other messages, I may NOT want to. I understand this forum is mainly for messages one WANTS to type. This is why this is an open forum.
AGAIN: IF THE MESSAGES I POST ANNOY SOME, I WILL NOT POST AS MANY AS I HAVE. I MENTIONED EARLIER: THIS IS LIKE A TOY FOR CHILDREN. Children get a toy, play for a while a lot, then less often, then very occasionally.
If you or anyone else believe the assumptions and presumptions, as you call them, are incorrect you can just post this and the problem will be solved. You can pinpoint what or just say in general. Whoever reads will not trust a given person but read everything, check everything and then decide.
I have NEVER been impolite in this forum but you may have left with a wrong impression.
I do NOT want to make a lot of effort to explain everything. ANY STABILISING, NEGATIVE FEEDBACK MAKES THINGS PERFECT. This is a very basic and true statement. The things must be designed to be stablised, though, not to have been designed to generate or oscillate. HOW PERFECT IS A GIVEN FEEDBACK IS ANOTHER QUESTION. You may play words with the word "PERFECT", there is no more perfect than perfect and there is no less, etcetera. The meaning is very clear, I hope, though.
Everyone needs help. Thank you for the good intention. Reading this forum is not the only thing I want to do but, yest, the more one reads the better. Even when something is simple and basic and well known. Better to be read even more. Again: I can always get a book or download online or read the forum. I do not want to do this ONLY, though.
Mistakes happen as I have mentioned and will continue to happen. The feedback is perfect is not a mistake but, I believe, misunderstanding of what one means. I can try to express this again with other words: A feedback is perfect means a feedback, when intended to stablise, perfectises the circuit as compared with the same circuit without the feedback. Obviously, there are different levels of feedback or different percentage with 100% feedback being what is what you have in a buffer. This statement for the perfect feedback is true NOT ONLY IN CASE OF SOUND OR ELECTRONICS BUT EVERYWHERE IN TECHNOLOGY OR WHEREVER A FEEDBACK CAN BE APPLIED, GENERALLY SPEAKING. The specific way you do the feedback: whether current, voltage or the toilet tank is irrelevant. Feedback is separate from the application. The science of the feedback is not electronics nor sound engineering but Automation. You may call Automation science rather than engineering also because Automation deals with feedbacks NOT ONLY in amplifiers or electronics but EVERYWHERE. Do NOT be insulted but sound is a place where feedback is used the least.
I have spent 15 minutes for typing this message. Also I have never wanted to type this or part of this message. If you really want to be polite, please, try to ask others what one may mean by saying so. There is nothing wrong if I hadn't explained this or you didn't understand. No one can understand everyone and no one can explain everything to anyone perfectly. This is why I have made a very clear point on terminology. Must not be used but, when necessary, use as tiny as possible.
If your point has been to read in order to find out I am wrong to think electronics is as simple as 2 + 2, though, this will be an insult. First I have seen enough, second even if I haven't, ONE DOES NOT NEED TO SEE A GIVEN THING IN ORDER TO UNDERSTAND WHAT THIS THING IS. This is why one can think. So, even if one hasn't seen electronics, one can analyse what thinking is necessary to be applied by a given person in order to achieve something. THIS IS CALLED PSYCHOLOGY and not electronics nor psychiatry. PSYCHOLOGY, SO THEY SAY, IS A SCIENCE OF HOW PEOPLE THINK. Please, ask a friend what I mean and do NOT be insulted, I do not mean what you may think. All I mean is for you or anyone else to ask a PSYCHOLOGIST what is involved in electronics by talking to this person of how electronics problems are solved and circuit designed. The psychologist doesn't need to know anything of electronics or sound. The psychologist will evaluate what kind and how much thought is necessary for electronics design. I do NOT want to spend more to communicate this to you.
I am 100% sure, a psychologist would tell you electronics is always very basic and primitive thinking at any level and, more, there aren't different levels of electronics, everything is 2 + 2 = ? There are different levels of mathematics but not different levels of electronics.
Of course, you may decide to enter a discussion what electronics means at this point but I do NOT want to. I have mentioned electronics is different than the mathematics and other "tools" used with electronics. Please, talk to a friend on this subject. DO NOT TAKE THIS WRONG: I don't mean to say you do not know electronics, I mean to say you do but to know electronics doesn't necessarily mean to know what electronics is. From talking to many people, I may say I am sure the best in the field, as you say, do not. This does not make them less best. Just one thing does not have anything to do with another. To know what electronics is and how electronics differs from the other sciences used therewith is a subject of field classification. This subject is not carried out by specialists in electronics. Not to sound bad, I will also continue to talk with various people what electronics is and what is subject of electronics and what is subject to other fields and sciences which may be used with electronics. To know all of this fields doesn't mean to be able to classify them on the contrary may mean inability to do so.
Also, I have spoken to psychologists on thinking, problem solving, etcetera. I say this just to know I do not play superior by saying this. You may also have. I don't know. If you have, then may I suggest we leave this topic to the psychologists with different opinions to decide and accept we cannot solve this problem.
The point I clearly disagree with you has been mentioned previously, but I will say this again: ENGINEERING IS ALWAYS BASIC. There aren't different levels. Again, we can leave this to be decided by people who are supposed to do this and we are definitely not these people. In case you are one of them, I am still not. But I have spoken to many who also are. I have already mentioned: this is a subject for people who deal with thinking, etcetera.
The budget is not an issue. The issue is the price. Even if I had all the money in the world, I would still look for a better price solution. Whether I will use such or not is another story.
I am able to purchase a good quality analogue amplifier from the 70's for less than $5, for example.
I have spent more than 1/2 hour for this message which I have not wanted to type. SOME of the messages I type, I may WANT to type. Other messages, I may NOT want to. I understand this forum is mainly for messages one WANTS to type. This is why this is an open forum.
AGAIN: IF THE MESSAGES I POST ANNOY SOME, I WILL NOT POST AS MANY AS I HAVE. I MENTIONED EARLIER: THIS IS LIKE A TOY FOR CHILDREN. Children get a toy, play for a while a lot, then less often, then very occasionally.
SSB,
I think you have a profound misunderstanding of how feedback works and what its effects are.
So, answer this simple question relating in part to "feedback" - If I have a higher gain in my amplifier and apply more feedback, will that give a more "perfect" amplifier?
And, along those lines, what level of THD is required in the real world for an amplifier in your opinion to be as perfect as is practical - in your opinon?
Thank you.
_-_-bear
I think you have a profound misunderstanding of how feedback works and what its effects are.
So, answer this simple question relating in part to "feedback" - If I have a higher gain in my amplifier and apply more feedback, will that give a more "perfect" amplifier?
And, along those lines, what level of THD is required in the real world for an amplifier in your opinion to be as perfect as is practical - in your opinon?
Thank you.
_-_-bear
I think you do not understand what you say. I will answer your feedback question BUT, please, find someone else to talk to in these issues who may understand what I mean. Here is the answer:
Assume you have the same open gain of the OA. If you feedback fully (buffer, gain=1), this is the most "perfect" amplifier you will get as far as the feedback is concerned. Now, assume you have the same feedback arrangement and put an OA with higher gain. You will have even more "perfect" OA. This is called 100% feedback: 100% of the output is returned to the input. The strait track (the OA) helps the feedback and self. The higher the gain the stronger the OA will PUSH the good parameters to be better.
Now assume the same two cases with overall gain. The more the gain the more you screw your amplifier as compared to the same with 100% feedback. When you compare the low gain IC with 100% feedback to the low gain IC with overall gain (not a 100%, not all of the output is returned, the output is divided through the feedback resistors and the division is returned). The same with the high gain IC. 100% good. Less than a 100% less good. Now, you have to do some calculations to compare high gain IC in any configuration with low gain IC in any configuration.
Therefore: THE MORE FEEDBACK AND THE MORE IC GAIN THE MORE PERFECT.
The buffer (100% feedback) has the highest input impedance, the lowest output impedance and the highest transmission frequency and is the fastest. As you put gain, you screw up these. An example which you know even when you sleep: The more gain you put the lower is the highest frequency to pass through the OA before the furst cut off. This is:
fc=ft/G, where fc is the first cut off frequency, ft is the transmission frequency of the IC (you know this as Unity Gain Bandwith), G is the overall gain defined by R1 and R2.
So, the more overall gain you put, the more you screw up the bandwith of the amplifier.
The same with the input impedance and the output impedance. The more G the higher the output and the lower the input impedance. You screw them up with G.
The higher the open gain A, the higher the input impedance and the lower the output impedance of the feedbacked system with whatever gain.
This is why, a good idea is to use a few IC's with lesser gain each as opposed to one with huge gain. BUT each IC introduces problems as noise and non linearity. Thus, do NOT do this or COMPROMISE.
So, therefore, the feedback makes a given amplifier more perfect. Even if you think you can make it more perfect by changing the IC with a higher open gain IC thus keeping the gain YOU WOULD MAKE THE AMPLIFIER EVEN MORE PERFECT BY USING THE HIGH GAIN IC BUT PUTTING LOWER OVERALL GAIN.
Perfect amplifier is an amplifier as close to IDEAL as possible. Ideal amplifier is one with:
* infinite input impedance
* 0 output impedance
* infinite ft
* infinite open gain
Please, read the posts. Some of these things are in the posts.
I hope this answer satisfies you.
I cannot write to you more. Please, post your games ONCE A WEEK. I want to do other things or to do nothing but I do NOT want to write what I do NOT want to write and you have always forced to write what I do NOT want.
For the record: I have spent more than an hour because of you today to do what I do NOT want to do. AGAIN: talk to someonce to `translate` what I mean.
Now another thing: make a buffer. Put a diodes in parallel but in differen directions AFTER the feedback. Put load. Increase the voltage at the input of the buffer gradually from 0 up. The diode is not linear and will start conducting slowly and a bit only until you pass 0.7V. Then the diode will continue to conduct still rising the voltage a bit up (after 0.7V). The diode is not perfect. The voltage does not stay at 0.7V but goes up.
NOW PUT THE DIODE BEFORE THE FEEDBACK. Increase the voltage slowly and a bit only. WHATEVER YOU PUT AT THE INPUT YOU GET AT THE OUTPUT. No changing 0.7V up non linearly with the current. YOU HAVE JUST PERFECTISED YOUR CIRCUIT BY PUTTING THE DIODE IN THE GENERAL FEEDBACK. You eiminated the diode problem. You also do not have to wait for more than 0.7V. You get what you want imediately. You pay only with decreasing the output range by 0.7V. The IC cannot go more than the maximum. When at maximum, this maximum cannot be displayed at the load. Maximum - 0.7V is your maximum.
But look how much you got!
Can you find someone else to bug, please. If you don`t like what I write DO NOT READ AND DO NOT REPLY!
So, please, keep your replies for a week. I do NOT want to write these things but I do want to write other things.
BTW, this principle applies NOT ONLY FOR OA BUT FOR ALL SYSTEMS WITH A NEGATIVE FEEDBACK: mechanical, pneumatic, whatever.
You said you wanted to be polite. Please, do. What you do now is definitely NOT. Respect other people`s desires as they respect yours. I have never writen to you. I have only replied to you.
Anyways, I didn`t want to be impolite and I didn`t want to dictate conditions but if you write again, you will not receive an answer for a while. Then you will if I don`t forget. THE ONLY REASON FOR THIS IS: I DO NOT WANT TO TYPE WHAT I DO NOT WANT TO TYPE AND I DO WANT TO TYPE WHAT I WANT TO TYPE.
Come to Toronto, we will talk. I can arrange a meeting with you and one of the superb Motorola designers. I will not be present and I will not talk nor listen. You can talk the phylosophy of electronics if there is such.
REMEMBER: ELECTRONICS IS BASIC, SIMPLE AND NEVER COMPLICATED. LEGO GAMES ARE MORE ADVANCED THAN ELECTRONICS. Please, talk to other people on these subjects: your friends, privately. They may be able to translate from what I want to say to the way you are used to hear this.
Assume you have the same open gain of the OA. If you feedback fully (buffer, gain=1), this is the most "perfect" amplifier you will get as far as the feedback is concerned. Now, assume you have the same feedback arrangement and put an OA with higher gain. You will have even more "perfect" OA. This is called 100% feedback: 100% of the output is returned to the input. The strait track (the OA) helps the feedback and self. The higher the gain the stronger the OA will PUSH the good parameters to be better.
Now assume the same two cases with overall gain. The more the gain the more you screw your amplifier as compared to the same with 100% feedback. When you compare the low gain IC with 100% feedback to the low gain IC with overall gain (not a 100%, not all of the output is returned, the output is divided through the feedback resistors and the division is returned). The same with the high gain IC. 100% good. Less than a 100% less good. Now, you have to do some calculations to compare high gain IC in any configuration with low gain IC in any configuration.
Therefore: THE MORE FEEDBACK AND THE MORE IC GAIN THE MORE PERFECT.
The buffer (100% feedback) has the highest input impedance, the lowest output impedance and the highest transmission frequency and is the fastest. As you put gain, you screw up these. An example which you know even when you sleep: The more gain you put the lower is the highest frequency to pass through the OA before the furst cut off. This is:
fc=ft/G, where fc is the first cut off frequency, ft is the transmission frequency of the IC (you know this as Unity Gain Bandwith), G is the overall gain defined by R1 and R2.
So, the more overall gain you put, the more you screw up the bandwith of the amplifier.
The same with the input impedance and the output impedance. The more G the higher the output and the lower the input impedance. You screw them up with G.
The higher the open gain A, the higher the input impedance and the lower the output impedance of the feedbacked system with whatever gain.
This is why, a good idea is to use a few IC's with lesser gain each as opposed to one with huge gain. BUT each IC introduces problems as noise and non linearity. Thus, do NOT do this or COMPROMISE.
So, therefore, the feedback makes a given amplifier more perfect. Even if you think you can make it more perfect by changing the IC with a higher open gain IC thus keeping the gain YOU WOULD MAKE THE AMPLIFIER EVEN MORE PERFECT BY USING THE HIGH GAIN IC BUT PUTTING LOWER OVERALL GAIN.
Perfect amplifier is an amplifier as close to IDEAL as possible. Ideal amplifier is one with:
* infinite input impedance
* 0 output impedance
* infinite ft
* infinite open gain
Please, read the posts. Some of these things are in the posts.
I hope this answer satisfies you.
I cannot write to you more. Please, post your games ONCE A WEEK. I want to do other things or to do nothing but I do NOT want to write what I do NOT want to write and you have always forced to write what I do NOT want.
For the record: I have spent more than an hour because of you today to do what I do NOT want to do. AGAIN: talk to someonce to `translate` what I mean.
Now another thing: make a buffer. Put a diodes in parallel but in differen directions AFTER the feedback. Put load. Increase the voltage at the input of the buffer gradually from 0 up. The diode is not linear and will start conducting slowly and a bit only until you pass 0.7V. Then the diode will continue to conduct still rising the voltage a bit up (after 0.7V). The diode is not perfect. The voltage does not stay at 0.7V but goes up.
NOW PUT THE DIODE BEFORE THE FEEDBACK. Increase the voltage slowly and a bit only. WHATEVER YOU PUT AT THE INPUT YOU GET AT THE OUTPUT. No changing 0.7V up non linearly with the current. YOU HAVE JUST PERFECTISED YOUR CIRCUIT BY PUTTING THE DIODE IN THE GENERAL FEEDBACK. You eiminated the diode problem. You also do not have to wait for more than 0.7V. You get what you want imediately. You pay only with decreasing the output range by 0.7V. The IC cannot go more than the maximum. When at maximum, this maximum cannot be displayed at the load. Maximum - 0.7V is your maximum.
But look how much you got!
Can you find someone else to bug, please. If you don`t like what I write DO NOT READ AND DO NOT REPLY!
So, please, keep your replies for a week. I do NOT want to write these things but I do want to write other things.
BTW, this principle applies NOT ONLY FOR OA BUT FOR ALL SYSTEMS WITH A NEGATIVE FEEDBACK: mechanical, pneumatic, whatever.
You said you wanted to be polite. Please, do. What you do now is definitely NOT. Respect other people`s desires as they respect yours. I have never writen to you. I have only replied to you.
Anyways, I didn`t want to be impolite and I didn`t want to dictate conditions but if you write again, you will not receive an answer for a while. Then you will if I don`t forget. THE ONLY REASON FOR THIS IS: I DO NOT WANT TO TYPE WHAT I DO NOT WANT TO TYPE AND I DO WANT TO TYPE WHAT I WANT TO TYPE.
Come to Toronto, we will talk. I can arrange a meeting with you and one of the superb Motorola designers. I will not be present and I will not talk nor listen. You can talk the phylosophy of electronics if there is such.
REMEMBER: ELECTRONICS IS BASIC, SIMPLE AND NEVER COMPLICATED. LEGO GAMES ARE MORE ADVANCED THAN ELECTRONICS. Please, talk to other people on these subjects: your friends, privately. They may be able to translate from what I want to say to the way you are used to hear this.
SSB,
thanks for the lengthy reply.
Only two replies were required:
Q1: yes or no
Q2: a number
you avoided a direct and simple response.
It is interesting to me that you may be the only one on here who thinks this is true, when you say "electronics is simple." It may well be so for you... like physics for Einstein?
Have you built any of your designs? Can you post pix? There are plenty of pix on here of prototype rat's nests, so no reason to be shy, afraid or concerned.
Looking forward to seeing these things...
thanks for the lengthy reply.
Only two replies were required:
Q1: yes or no
Q2: a number
you avoided a direct and simple response.
It is interesting to me that you may be the only one on here who thinks this is true, when you say "electronics is simple." It may well be so for you... like physics for Einstein?
Have you built any of your designs? Can you post pix? There are plenty of pix on here of prototype rat's nests, so no reason to be shy, afraid or concerned.
Looking forward to seeing these things...
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