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Is there any way I could adapt this design to use a standard 3 input wire pp opt? I would like to try bread boarding it, but I would like to use a pp opt that I already have, the hammond 125e. I know it's not the best match, but it would it be a cheap way for me to get to listen to it.
Edits: 09/25/17 09/25/17
vinnie,
you need to "triode strap" the output tubes. connect a 100 ohm resistor from the screen of each 6v6 to their plate. read up on triode strapping pentodes if you want to understand what you are doing.
you then need to remove the global feedback loop. it is attached from the 16 ohm tap on the secondary of the output transformer to the top of the cathode of the 6sl7 input stage. the 1k resistor and bypass capacitor arew what you will remove.
that circuit appears to me to be using a floating paraphase input stage to split phase and drive the output tubes. I don't care for that style of phase splitter.
if the phase splitter still works after those changes you'll have a circuit with a lot of gain and not a lot of deep bass. you'll also probably have a lot of imbalance in the phase splitter resulting in a good deal of 2nd harmonic distortion. I personally have not been able to make the floating paraphase work. I prefer a differential pair with a ccs in the tail.
triode strapping the output stage removes the need for feedback and lowers the gain of the output tubes.
removing the global feedback loop increases the gain of the entire circuit.
the rest of the group feel free to correct me I won't take offense.. I am here to learn.
Thanks for the info rage. Based on your comments and a few others, I have decided to look around for a design that better fits my opts. Thanks again.
Edits: 09/28/17
Vinnie happens to be correct in regard to the Hammond 125xSE series of opts being excellent. I have used them almost exclusively since they were originally introduced. The key is to run them at far below their rated wattage. Doing so allows them to provide phenomenal bandwidth, and the resultant sound quality easily surpasses that of many more highly regarded xfmrs. This point was clearly demonstrated by George Anderson years ago with his measurement of the CSE version, and my own measurements support his:
He is asking about the E version which is a low cost PP OPT
That is why I asked if he had tried it.
Edits: 09/28/17
The ESE is good in a budget SE amp. And that's what Tubelab sells as kits.
If you rea going to build a high quality SE amp using true troides, the 125SE series would not be a good choice.
You are welcome to your opinion. Use what you want and I will use what I want.
Edits: 09/28/17 09/28/17 09/28/17 09/28/17
Hammond says, "Designed for general purpose or replacement use (not Hi-Fi) in single ended tube output circuits.
Frequency response: 100 Hz. - 15 Khz (+/- 1db max. ref. 1 Khz)"
gusser said "If you are going to build a high quality SE amp using true troides, the 125SE series would not be a good choice."
Why do you call that an opinion?
Hammond says the same thing on the data sheet and for good technical reasons.
My EP SE OPT Frequency response is: 28Hz - 57Khz (+/- 1db max. ref. 1 Khz)
Do you think that the difference between the two transformers will not be heard and that technical truths and numbers don't matter?
If you do then you are wrong.
You can use any OPT you like but don't fool yourself into thinking that the Hammond is the equal to other technically better transformers.
They are not.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Did you read the post by SETguy? His post and the link he gave match my own experience. That why I call it an opinion, because my own experience with them is different.
Edits: 09/28/17 09/28/17
Yes I did read his post and the link.
"Electra-Print
These are the reference transformer, I have found nothing better for this amp."
"The Electra prints obviously are not afraid of any of these transformers"
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Yes, at twice the price. He states in his article that the hammond is his budget opt of choice. My whole point is that for me it isn't worth the higher price for the extra 5% I might get in sound. It's a cost/benefit analysis on my part. I'm on a fixed income now, and I have to make sure I do not spend money I do not need to if I want to build projects. Besides, at the rate I change which amp is my current main squeese I would go broken using the high priced spread considering I give some of them away.
Edits: 09/29/17
I have no problem with what you just said.
But the EP transformer is a better transformer with more frequency extension and that is not an opinion, it is just fact.
If the Hammonds work for you that's fine but don't try to say that they are better than the EPs or try to say that people that say the EPs are better than the Hammonds (and the EPs are better than the Hammonds) are just stating their opinions.
Facts really do exist and you will understand how electronics work much faster once you recognize that.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Will you PLEASE stop putting words in my mouth. I never said anyone was better than the other. I said that the 125ese provides a lot of bang for the buck. Each person has to decide for themselves how much bang they want to purchase. Others then jumped in and started spouting numbers to prove the 125ese was no good at all and that is just not true.
Edits: 09/29/17 10/02/17
Oh such heresey! : ) I just hope you don't get verbally stoned for daring to say such things on this forum!
I glad there is at least one other person out there that knows that the specs don't tell the whole story everytime. I have been using the 125ese for many years and have always been happy with its peformance.
Have you had any experience with the 125e? Just wondering if the same applies to it as the 125ese. I have not had a chance to try my pair out yet. Still looking for the right PP design to try them on. Thanks for the post.
Edits: 09/28/17 09/28/17
Those cheap Hammonds saturate quite abruptly . I am pretty sure Hammond intends these to be used in guitar practice amps
George
You may be correct about their intended use, but their big brothers, the 125ese are also marked "not for hifi" in the catalog, but are in fact quite good as a lower cost SE opt with the right tubes. I was hoping I might find the same thing true with the 125e, but have yet to find the right design to try them with.
Edits: 09/27/17
Thanks for the replies guys.Would this be true with all 6v6 pp designs? I really don't want to buy another set of opts just to try this, so I guess I will look for another design to try instead.
Thanks again
If you want to build around your Hammond transformer, use tubes that require low load impedance, like 50L6 or 6Y6, and lower B+ voltage.
Keep the fact that the 125E is an inherently POOR performer firmly in mind. Having said that, the nL6 is a reasonable recommendation. Power O/P will mesh well with the 125E.
The originally proposed schematic employs a B+ rail that's too "tall" for the nL6. The sort of circuitry Jeff Yourison used in his 6Y6 project will work nicely. Change the 0.1 μF. cap. at the I/P to 0.033 μF., to protect against core saturation. F 3 is still below the lowest note (41 Hz.) a "standard" double bass produces.
Eli D.
I keep hearing that, but it doesn't jive with what my ears tell me, nor apparently with what Don Garberes ears told him. Take a look about half way down the attached link (just into the green tyoe a little) and you will see that he offered the 125ese as a standard level opt on his SE "X" amp, and I have used that one also for a long time with very good results. After using the 125e a few times for bread boarding, I am inclined I think numbers don't always tell the whole story and that the hammond opt's have gotten a bum rap. You do have to use it with the proper tubes however, no escaping that.
Edits: 09/26/17
Don't take this the wrong way but you may have some hearing loss.
Or maybe you have a very "live" listening area that boosts some frequencies. Concrete or tile floors can do this as well.
Do a frequency sweep with a signal generator as a quick test to check transformer. You can run it thru your speakers as well.
I don't always believe what I read on the internet unless I see or hear it.
I'm an old coot so I am sure I have some hearing loss, but I am also talking about a respected amp builder (Don Garber) and several other sources (as well as my own ears) who have said that the 125ese was a lot of opt for the money. I don't know about the 125e yet as I have not found much on it and I am still looking for a good pp design to try them out on. I am the same way about seeing and hearing as you are, but watch your back, because that is heresey to some on this forum. They think if it isn't a number they can measure it doesn't exist.
Edits: 09/27/17 09/27/17
"They think if it isn't a number they can measure it doesn't exist."
Nobody in this discussion thinks that. You're just grasping at straws, looking for a way to discredit the factual information provided by the manufacturer.
--------------------------
Buy Chinese. Bury freedom.
For pete's sake, TK, darn near every time you turn around you are making a comment about how something can't be measured or something has not been proven or some thing like that. You are never willing to accept what your ears are telling you or someone else. So what do you call that except not willing to accept anything you can't measure?
Edits: 09/27/17
Denial of this issue - to the point of taking personal offense - is a big problem in these discussions. It's simply not possible to reach a mutual understanding when the other party refuses to accept fact.
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Buy Chinese. Bury freedom.
People will have different expectations/standards... and ways of achieving them. This runs deep into ego (beliefs and self-worth) - hurt and defensive (offensive!) reactions will often result from conflicting beliefs.Less and less, I expect myself to convince other DIYers; my opinions are just that, my narrow opinion. I try to learn from others and personal experience and perhaps share when I think it might help, which is not often these days. But I try to make it about helping, not forcing my opinion on others. I'm not always successful.
Cheers,
91.
"Confusion of goals and perfection of means seems to characterise our age." Albert Einstein
Edits: 09/27/17 09/27/17
I suggest you listen to your own advice TK. You refuse to accept the fact that just because something isn't in a text book or a spec sheet doesn't mean it can't be real.
You're not describing fact. That's why I don't accept it.
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Buy Chinese. Bury freedom.
They are facts that you won't accept because they don't fit your narrow little plan of the world.
125ESE is TOTALLY different from 125E. Aside from the PP vs. SE matter, the SE models are a more recent offering.
Eli D.
I actually "TRIED" a ESE in a cheap SET build. The ESE is a low cost SE OPT that has reasonable specs.
The E series was designed for console stereo and the like replacement use. Good, but certainly not HiFi.
Bum rap? Even Hammond says "NOT HI-FI" to both of these. No, it doesn't matter which tubes you drive them with. NOT HI-FI.
--------------------------
Buy Chinese. Bury freedom.
Have you ever tried one TK? Don Garber thought the 125ese was "hifi" enough to offer it as an option in his "X" amp. Also in an article in Sound Practices" magazine he said the difference in the sound of the amp with the 125ese or the high priced spread "was not as much as some people would like to think". If you haven't tried a 125ese you should. I think it would surprise you. Hifi would capture the extremes of music, but how much of recorded music actually uses those extremes?
Edits: 09/26/17 09/26/17 09/26/17 09/26/17
"not as much as some people would like to think"
Don Garber isn't here to tell us exactly what he meant by that, or why he thought it was appropriate to offer a less-than-optimum transformer in his amplifiers. The specifications (and the manufacturer) speak for themselves. It's a limited-bandwidth product intended for the low-end market and non-hi-fi applications. Rationalize the performance all you want, but you're only fooling yourself if you think these transformers can be used to qualify tube types or amplifier topologies. As for the extremes of music, they're extremely important. Music is flat, dull and lifeless without them.
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Buy Chinese. Bury freedom.
And you are only following yourself if you think there is nothing else out there to use but "hifi" parts that are capable of giving the average listener good sound. Do a little surfing on the web TK, and you will see that a lot of folks think the 125ese provides a lot of opt for the money. That's why Don offered it, for the people who didn't want to spend a lot more for just a little improvement. If you do, be my guest.
And you still haven't answered my question; have you ever tried one?
Edits: 09/26/17 09/26/17 09/26/17
No, and I've never driven a Yugo or a Trabant either. I have no desire to waste money on products known to be inferior.
--------------------------
Buy Chinese. Bury freedom.
That's what I thought. You know for quite a few years they thought it was technically impossible for the bumble bee to fly, at least they couldn't understand how he did it. Turns out they were missing some information and using the wrong criteria in their calculations. That's why you have to use your ears too TK, numbers don't always tell the whole story.
Edits: 09/26/17
Is that what you are saying?This stupid "have YOU tried it" argument! It always comes from novices that refuse to learn first.
"12 volts across a 1 ohm resistor is 25 amps!"
"No, because based on ohm's law..."
"Well have you tried it?, How do you know for sure its wrong"
Edits: 09/26/17 09/26/17 09/26/17
No dipstick, I am saying that the math doesn't always tell the whole story. But I would not expect you to understand that.
it just needs somebody with experience to decide when enough of it has to be put in place. And then an attempt at solution needs to be done.
Gotta be able to recognize when there isn't one...or that it won't converge.
The whole 1%-er Hi-Fi Nut is entirely divorced from this. They seem to want to create their own reality that is answerable to none but their Priesthood. In that scenario, they get exactly what they deserve...:)
cheers,
Douglas
Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
"The whole 1%-er Hi-Fi Nut is entirely divorced from this. They seem to want to create their own reality that is answerable to none but their Priesthood. In that scenario, they get exactly what they deserve...:)"
For a non-technical audiophile, it is easier to follow a reclusive guru and purchase his bespoke high-end $$$ gear than being DIY.
That person can get the feeling of being part of an elite 1% audio society and enjoy all the posturing, bravado and one-upping that goes with it.
For some, this is an enjoyable aspect of the hobby.
There is however a middle ground where you don't follow any guru, technical or otherwise. Instead you try to learn what you need to know to do what you want to do. That is NOT the same for every person as we can each want different things from the hobby. In my case it's building and bread boarding tube gear. I don't need to know how to design it with all the schematics already in existence, but what I do learn helps me along the way. But not having to spend many hours learning the tech stuff makes it more enjoyable for me. For some people the tech stuff is what it is all about and the building is just a side option. No reason we can't coexist except when one side starts saying you must bow to our superior knowledge and qualifications, we are the only ones who know anything.
Edits: 09/27/17 09/27/17
But vinnie, do you stick to "schematics already in existence"?If you stick to building proven designs verbatim, you might still benefit from learning how to build well, test and troubleshoot... but you will still need some understanding of theory to do this.
By contrast, if you are changing values and topologies, you would benefit from learning the basics of analysing simple tube circuits (Ohm, Kirchhoff, basic tube parameters).
Invest some effort in learning some fundamentals - it will be worth it even if you are not interested in comprehensive design.
Cheers,
91.
"Confusion of goals and perfection of means seems to characterise our age." Albert Einstein
Edits: 09/27/17 09/27/17
The trouble is I know what "learning some fundamentals" involves, and it takes years of time that I don't have. If I stick with good designs I have no problems. If and when I want to changes topologies or values I come here, which is what I have always thought this forum was for, among other things, based on the forum by-line.
I see it differently. Plenty of resources exist to get some basic knowledge quickly. Having that knowledge provides a better understanding for troubleshooting and asking questions. It helps develop your craft. Get the basics, then fill in the detail at your leisure.The alternative is to gain from others' good intentions to help without doing the work. Sure, the forum is here for help, but that does not mean you are entitled to help from others just because you want it without putting in some effort to learn... or to learn enough to help others. But, that is a "values" argument that can be spun myriad ways... I'm not "right" in this. Still, I would not derive enjoyment from continually taking.
edit: removed the final para that counter-productive.
91.
"Confusion of goals and perfection of means seems to characterise our age." Albert Einstein
Edits: 09/28/17
I learned it in one night. For me, it's a lazy way of experimenting without doing the math by hand or picking up a book. And will answer a lot of these questions. I simply experiment with values until I get the results Im looking for.
If interested, I'll send you a link to my google drive which already has all the files you need along with tons of schematics. Simply copy the entire directory to HD and your done
Edits: 09/28/17
You should have access and be able to right click and download. Once you download, copy the directory to your drive and execute scad3.exe from the LTspiceIV subfolder. Move the Schematics to the LTSpice folder so it reads the library files correctlyCheck out spreadsheets in tools folder, I use this for OPT numbers in some asc files
Start playing around with existing schematics. If you have "Teamviewer" or gotomeeting, I can log you in one night and show how to simulate and display the results, it would probably save you some reading. I'm not an expert and know enough to get you voltage, current, power and distortion figures. It's easy to "google" how to do this as well.
Warning: There's a few unfinished circuits I experimented with so proceed with caution. Once you sim for distortion, gain and some other parameters it will become apparent. Some circuits are copies of published circuits or circuits from this forum.
I can create a collaboration folder(read/write) on my sharepoint for those of you that want to collaborate and share some files/idea's
Enjoy
Edits: 09/28/17 09/28/17 09/28/17
Spice is great for testing designs and to some extent bypassing the complex mathematics although that's not it's intention.
You still have to know how the circuits works in order to design it in the first place. And you are still required to do the basic math to get "into the ballpark" of the desired circuit operation.
Correct, but you can study other schematics and use similar circuits to inject in your circuit to get these ballparks. Once you do that, its a matter of tweaking the values until you find the results. After you do a couple schematics and get the hang of it, you'll learn to get the values closer each time. For me, I did very little tweaking once I bread boarded. Think of it as a stepping stone and visualization to actually understanding how the circuit works(learning theory). Some simply learn quicker than reading a book. I have learned a lot with this program and the help of this forum. If I ever retire, I'll start reading more....Thanks for all your help!
I've learned much more doing it your way than by reading, although I do also read. But messing with values in a real circuit to see how parameters are thus affected is something you don't forget about.
Would really llike to have that!email is vince@vrhea.com
Thanks!!
Edits: 09/28/17 09/28/17
deafbyukhorns,
I'd love a link for what you have offered vinnie... learning ltspice has been on my list for some time!
.
I would like to have access to those sims.
Thanks.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Send me your email address in a PM
Me too please pretty please :)
usedhifi@mail2lawrence.com
First of all I feel I have contributed almost as much as I have "taken" in that I always report the results of my efforts (good or bad) so that others may learn from it.
Second, I have never felt that I am "entitled" to anything. I appreciate all the help I get, but if someone doesn't want to spend the time helping me they can go on to the next post. Doesn't hurt my feelings at all.
Third, from what I have seen, I am a long ways from being alone in inaccurate descriptions or vague questions. When a person is asking for help that happens quite often. Otherwise they probably would not be asking for help.
Fourth, the only people I snap at are those that take on a high and mighty air of how knowledgble they are and how dumb everyone else is. That is definetly not in the spirit of this forum.
I don't agree... and noticed you conveniently avoided the main point. No bother, we're human so that should be expected.
91.
"Confusion of goals and perfection of means seems to characterise our age." Albert Einstein
I did not avoid it, it was just too obvious to answer. Of course more knowledge helps everyone. The point you have missed is that I would rather learn by doing when I can, not spend my time with my nose buried in a text book.
Evidence shows you have been on this forum since at least 2008. It's hard to believe in all that time you never learned how to triode strap a pentode. That has been illustrated at length here and on many other tube audio forums.Now you were told how about two weeks ago in an SET. But you are asking the same basic question for a UL design. It's the same theory and principle.
This is very basic stuff you need to know in order to build tube amps especially if you are going to modify the design which you do quite often. You claim to be just following schematics but in reality you are re-engineering many of these designs. Converting a UL topology to triode or using radically different tubes is re-engineering. And to do that you have to know how the circuits work.
Edits: 09/28/17
If you don't want to answer my questions, don't. I can do without your snide comments thank you.
Let me rephrase that to "the math will only take you so far".
"the math will only take you so far"
That may be, but just keep in mind that without the math you will get nowhere at all.
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
Agreed, someone has to do the math, but if you are a builder and you have a good schematic you will do just fine. That has been my point all along.
Vinnie, the problem is, I have never seen you do that.
You may start with a schematic but then you want to change it or you don't have the exact parts, etc.
But you don't know how to change it because you don't know/understand the math and you come here asking questions. Then you argue with the knowledgeable people (who do know the math) who are trying to help you.
If you were to just build a schematic using all the exact parts the schematic calls for, then the unit would just work (assuming the schematic is for a proven design) and you wouldn't need to know any math.
I have yet to see that happen with you.
If all you want to do is build a proven design from a schematic then get all the exact parts that the schematic calls for (so you don't run into anything that you would need help with) and build it.
At that point you wouldn't need to know the math but as soon as you want (or need) to change something then you do need to know the math.
In all seriousness,
Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"
In all seriousness Tre', what do you think is the purpose of this forum? I really would like to hear your answer to that question.I start with what I think is a proven design (sometimes it isn't) and then if there are glitches or I what to try a "what if", I come here for help. I have always believed that is one of the main purposes of this forum. Has anyone even read the by-line? "Do It Yourself (DIY) paradise for tube and SET project builders." That seems pretty clear to me. What else would "project builders" do but help each other and discuss their projects?
As far as arguing with people, it is usually with people who are more interested in showing everyone how much they know or think they know, rather than helping people. That is not at all in the spirit of what I think the forum is here for.
Edits: 09/28/17
"As far as arguing with people, it is usually with people who are more interested in showing everyone how much they know or think they know, rather than helping people. That is not at all in the spirit of what I think the forum is here for."That's not entirely accurate. I once merely offered a suggestion that your component layout was in contrast to good RFI engineering practices.
You jump on any suggestion like that saying it that worked for you therefore it's good. That's not helping other people at all. These guidelines and theories are built on not only solid physics but in many cases learned from failure. You are basically telling everyone that the written rules are wrong and not need to be followed. And at the same time you admit you have no background in electrical engineering but more importantly you have no desire to learn it.
To call it closed minded just because you broke the rules and got away with it is hardly discovering new ground.
Edits: 09/28/17
I am through discussing anything with you gusser; it's like talking to the wall.
I am addressing the discussion at large and will continue to do so.As for "talking to the wall" I think the consensus here sees that as trying to talk to you.
Edits: 09/28/17 09/28/17
last word
!
The Mind has No Firewall~ U.S. Army War College.
Please make your post a little less mysterious. I do not understand your meaning and I want to make sure I do before I reply to it.
.
"Confusion of goals and perfection of means seems to characterise our age." Albert Einstein
That revision is BS too. Short sighted. A crock...
cheers,
Douglas
Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
Please explain your reasoning.
In this discussion, I will leave you with the following: You First.
Go build something. There are plenty of schematics on the web....LOL Aside from asking around here, how do you know when you have found one worth reading? ( LMAO! at your situation ) let alone worth buying parts for?
cheers,
Douglas
Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
My "situation" has allowed me (with help from some good people here at the forum) to build or bread board over 35 pieces of tube gear in the last 15 to 20 years. There is a multitude of information and schematics available through the internet and publictions like Sound Practices that have more than enough project schematics to last me the rest of my life. They also give information on if they are good designs.
I do fine except for those posters who seem to think that you have to have a Phd in EE to enjoy this hobby and strut around beating their chests and telling the rest of us what dummies we are. I know for a fact if all you want to do is build, all you need is a good schematic and the ability to read it, and enough common sense not to stick your paw into a hot unit. So your question is easily answered if anyone wants to build (not design) their own gear and takes a little bit of time to find some good schematics. Used to be they could count on folks here helping them through any rough spots. I hope that hasn't changed.
Edits: 09/28/17
I don't like doing this. I think it is important for you to understand why it would be helpful to learn some basics. I suspect you need direct responses - general explanations are not enough to convince you - so here goes:
"My "situation" has allowed me (with help from some good people here at the forum) to build or bread board over 35 pieces of tube gear in the last 15 to 20 years."
Despite building 35+ breadboards/ amps, you continue to make rookie errors and often ask vague or confusing questions containing misinformation. It is a time and energy vacuum for those who are trying to help. Every builder has these moments, but they are occasional. Understanding some basics would help you understand how the circuit works, which in turn supports better troubleshooting and communication.
"There is a multitude of information and schematics available through the internet and publictions like Sound Practices that have more than enough project schematics to last me the rest of my life. They also give information on if they are good designs."
And yet you don't seem to be learning from the information provided (see previous comments).
"I do fine except for those posters who seem to think that you have to have a Phd in EE to enjoy this hobby and strut around beating their chests and telling the rest of us what dummies we are."
You don't do fine Vinnie; you throw tantrums and externalise your problems. I'm not EE (by any stretch), don't expect you have to one, and don't think of you as a dummy. Yet you have personally insulted me when I have not agreed with you; I'm not alone in that. You may interpret someone as "...beating their chests and telling the rest of us what dummies we are", but is that really what's happening? You are responsible for your own actions.
"I know for a fact if all you want to do is build, all you need is a good schematic and the ability to read it, and enough common sense not to stick your paw into a hot unit. So your question is easily answered if anyone wants to build (not design) their own gear and takes a little bit of time to find some good schematics. "
Your builds and questions don't support that assertion. Anyhow, it is a strawman argument because you are actually re-engineering designs; you are not just building proven designs.
"Used to be they could count on folks here helping them through any rough spots. I hope that hasn't changed."
I don't think the helpfulness of the forum has changed much. I do think there has always been an expectation that a person asking questions has a basic level of understanding of what they are doing. I've read past posts where builders have been told to learn some basics before asking further questions. It is not unprecedented.
Well, that's about it from me on this topic. I've tried.
Take care.
91.
"Confusion of goals and perfection of means seems to characterise our age." Albert Einstein
If you don't want to answer my questions, don't. As for the rest of it, I am tired of some people telling me what I should be doing or learning when I am one of the few people on this forum who is actually building anything from what I can see. If others are, they sure aren't sharing it with anyone. There might be 4 or 5 of us that are posting pictures and reporting on how it's going. It would seem there are a some people here who talk a build rather than do it. This is supposed to be, and I quote, "a paradise for tube and SET project builders."
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I agree Vinnie, some of us do not share everything! I continually build/modifiy almost everyday, IMMHO I think you enjoy pontificating on this forum.
for me right now in this time I am mostly interested in wire mods its amazing to me how different wire can make components sound, this IMMHO does not require much knowledge but a good ear :) just make sure you use correct voltage spec wire...experimentation the "discovery" that I live for
for everyone else Vinnie is not 20 years old! he is 70+ and people of his age unless in elite health do not like to learn/understand new things my father is 71 and he is the same way and in his younger years did all kinds of electronic stuff... now I run circles around the old man :) fortunately for me I love to learn, I am 46.. getting older but still run with the youngsters :)
I am an active, productive scientist at age 74, and I still love to read books, articles, and papers both within and outside my area of research, including articles and books having to do with tube electronics. Age (apart from the effects of dementia if it pertains) has nothing to do with it, except maybe it makes you pig-headed about likes and dislikes.
lew your taking it personally, my comments are not aimed at anyone one person.
I am speaking from experience, I live in a community of mostly retired 70+ people, what I am saying is absolutely true in the majority, it has nothing to do with dementia, I believe it has lots to do with people who are diabetic who have hi blood pressure etc. etc. its the drugs that do this IMMO, whats more is some of these people have lived for 70+ years and think they know everything! LOL
its even worse now that the snow birds are back, terrible drivers!
now I think I am the minority on this site being much younger :)
We have a mix up on not wanting to learn vs wanting to learn by doing. Learning from electronics texts is boring to me, while learning by doing is fun. That is really all there is to it. As for pontificating, I think there are a few others here more into that than me.
all good vinnie!, just keep on.. keeping on.....
at least your doing more then my dad, he just likes to use his "remotes" and watch tv anymore, I try to include him in a project but he just don't get it! or want to learn anymore.
You're right vinnie. You are a beacon of hope to this forum.
Seriously though, you are posting your builds... but what are they contributing?
I'm more focussed on quality than quantity; with limited discretionary time available, my builds progress slowly. Presently, arranging a custom chassis build has brought my project to a standstill.
91.
"Confusion of goals and perfection of means seems to characterise our age." Albert Einstein
And that's just fine if that's what you want to do. We are all in this as a hobby and I hope to have fun and enjoy ourselves. As to what they are contributing, I like to think that it shows prospective new hobbiests that you do not have to have a EE to enjoy it and build some great gear.
Edits: 09/29/17 09/29/17
On these two:
"Used to be they could count on folks here helping them through any rough spots. I hope that hasn't changed."
I don't think the helpfulness of the forum has changed much. I do think there has always been an expectation that a person asking questions has a basic level of understanding of what they are doing. I've read past posts where builders have been told to learn some basics before asking further questions. It is not unprecedented.
**************************************
It is not just an assumption that a basic level exists, but that expanding it to a level beyond basic would be welcome, instead of belittling such understandings, and labeling them as unnecessary.
Anyway, as far as building w/o understanding...go for it. If you wish to remain ignorant, that of course is a right. It is my right to think such actions exceedingly foolish, short sighted, and counter productive.
I have no EE degree of any level, not even an Associates 2 yr paper...LOL
cheers,
Douglas
Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
See post above.
Look...you ask about triode strapping pentodes for a SE app( after finding notes for PP )...and then carry on this, 'I refuse to learn' jag. I would suggest being less surprised when you encounter people who have low or negative respect for such actions.
cheers,
Douglas
Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
No, not "I refuse to learn", but rather I am not going to spend what little time I have reading material in text books when I can be building instead. I will learn what I can from building and trying different things.
You have spent more time on this particular subject/discussion/thread than it would have taken you to learn the few things you'd need to move forward on your own.
cheers,
Douglas
Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
Not true.
Edits: 10/02/17
I hope you eventually discover how mistaken you are, and move away from this mind set you seem so fond of.
cheers,
Douglas
Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
That's funny, I was hoping the same for you.
Skip the name calling or find another place to play.
Thanks!
Fax mentis incendium gloria cultum, et cetera, et cetera...
Memo bis punitor delicatum! It's all there, black and white,
clear as crystal! Blah, blah, and so on and so forth ...
Math clearly proves that those transformers do not go beyond a specific frequency range albeit with a roll off curve. That said range is the common accepted performance for HiFi sound reproduction.Now what one may consider acceptable performance based on their personal hearing preferences is another matter and no current science can determine that. Well to a point. We do know placebo is very much at play here. If one spends many hours building an audio amp, of course it will sound good to them.
Again you asking very elementary questions here such as the differences between triode, pentode and Ultra Linear topologies. Yet you insist on arguing with the more experienced and then claiming they don't know everything, or is that "closed minded" when you don't like the answer.
Why not open YOUR mind and learn the operation theory of how these circuits work. You don't need to learn the intense engineering design details but even a service technician has to know how the basic circuit works.
Edits: 09/26/17 09/26/17
last word
"If you want to build around your Hammond transformer, use tubes that require low load impedance, like 50L6 or 6Y6, and lower B+ voltage."
The tubes don't determine the operating impedance of the circuit. That's created by the load reflected back to the tubes from the speaker. The 125E provides multiple primary impedances from 3K to 22.5K with an 8 ohm speaker. I assume that the specification of 2.99H is measured across the highest impedance option, and that the inductance decreases as lower ratios are selected. This is wholly inadequate for hi-fi use; best relegated to a communications receiver or answering machine.
--------------------------
Buy Chinese. Bury freedom.
I totally agree with Eli. The spec is 2.99 henries, frequency range 150Hz to 15kHz.
But for the record, to answer the question as asked, you can tie the screen grids to their plates (triode mode), or to the high voltage (pentode mode).
Regulating g2 B+, at a fraction of anode B+, deals with the lack of UL taps. Unfortunately, the 125E is completely inadequate. You need magnetic headroom to support the GNFB loop. Also, the 125E has limited low freq. extension. The 125E's core will saturate, if used in that circuit.
Edcor's CXPP25-8K will allow you to use that setup, with minimal fuss. The proper value of the phase compensation cap. (1000 pF. as drawn) has to be determined, by experimentation, at the bench.
Eli D.
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