THE DUALITY OF THE MAGNETIC REVOLUTION OR THE YING/YANG OF THE TRIODE REVOLUTION
You may not believe this but I was once six foot six, but because of the enormous burden on my shoulders I am now only five foot six and half inches. I have paid a terrible price for caring about the progress of the audio arts. I probably could have been a Hollywood movie star or a super model if I didnt care so much about small glass objects that glow in the dark.
Having said that I may soon be shrinking once again because as I take on the burden of agitating you all on the subject of magnetics I am dealing with one of the heaviest subjects in the audio arts...perhaps the heaviest. And I wouldnt be doing my job if I didnt take my usual radical approach.
I am a passionate OTLogists, which means I am keenly aware of the impediments on performance created by any transformer, yet I love transformer coupled amplifiers, and that naturally implies that I am very demanding of OPTs, and if you are addicted to directly heated triodes what choice do you have? My recent article about the Sun Audio amplifiers and my ranting about the high transformer quality standards demanded by Japanese audiomaniacs was the beginning of this crusade. I too once collected the classic American iron and had to own the gem-OPTs created by the American masters. In the 1970s I even took a class trip to the original UTC transformer factory in Brooklyn to see how they made their works of art (UTC has been revived by OPT industries in N.J.) The Japanese rightly believe that at one time American transformer winders were the best, and that was, to a great extent, true because of the transformers that were made for all of that tube military gear.
There is only one real reason that we are seeing a literal explosion in magnetic/transformer creativity: YOU. Your ascending sensitivity to music, your demand for a more refined musical aesthetic is the engine of the world wide magnetic revolution.
Of course the area that is receiving the greatest amount of attention is single-ended circuits and this is the most interesting creative paradox in the audio arts, and it reminds me of my own passion for Volkswagen and Harley-Davidson engines which I have hot rodded for decades. Both of these motors were designed in the 1930s and by modern standards are positively antique....yet....want to use a 350 hp VW motor at the drag strip?.....or want to build a nitro-methane burning supercharged 600 hp Hawg motor that will propel you down the track and straight to Hell? Our 1930s single-ended circuits have received the benefit of the same type of 100% sublime masculine creativity that we put into our cars and motorcycles, and we have transformed the archaic into a le plus modern musical aesthetic....same circuit concept with better quality parts, better quality magnetics, and a new generation of directly heated triodes.
And like the VW and Hawg motor we have to wrestle with the design limitations of SETs which is the output transformer which were originally designed to produce a whopping under 1 watt. What do we see today? 100 Watt SETs from Nobu Shishido and WAVAC, and more and more men wanting one tube 20 watters.
Your SET OPT is the weak link in your amplifier so we will now pause for one moment to do a profound calculation based on this question: If the SET OPT is so weak how can SET sound so magical? The answer is that there is such an inherent advantage in the simplicity and whole-osity of the SET that even when we subtract the weakness of the SET OPT we are still ahead of the game. It naturally follows that if we can minimize the limitations of the SET OPT we would achieve a major advancement. You will notice I included an article by Scott Frankland on the TG web site which explains these weaknesses of the SET OPT/speaker interface in detail, and again I emphasize the importance of using the right speaker with SETs. It is worthwhile to research back issues of Glass Audio for discussions about SET and you will discover serious engineers saying....Wow these circuits sound so great, but Golly Gee, they seem so poorly designed...what is going on here?...which should tell you something about audio orthodoxy.
We now understand the driving force of the new magnetic creativity: design a SET OPT that minimizes the inherent limitation of the design. As you would expect with any development work in the audio arts we are dealing with black magic and voodoo, because translating the science of magnetics into the art of music is not a reasonable pursuit for a sane man.
Which is why we have such passionate debates about OPTs and that is a good thing, and the subject of the articles which will appear under this heading. Yes the debate about silver vs. copper wire, the virtues of different steel laminate composition, and winding techniques are important because we are now getting down to the atomic level of music, and how can you be more sensitive than that?
I will be insisting that transformer designers contribute to this
section so we can understand their creativity.
LETS GET VERY SMALL
Another way to look at the current revolution in the audio arts is to look at it as YOUR ability get very very small. You are prepared to investigate the smallest details of your audio system because GOD makes Herself present in the smallest details (This is conventional wisdom when crafting your custom Hawg). You cant get any smaller than the electron level and when we are dealing with magnetics we are dealing with harmonics of electrons (which in spite of their small size is still larger than some of the brains in the audio business). Just think of a transformer as a magnetic coupling device.
As you know I started my career as a critic of magnetic coupling of tube amplifiers which is another way to say that I was and still am an OTLogist. There are three ways to connect a speaker to a tube amplifier...(1) through magnetic coupling/transformer (2) directly to the tube, or (3) through a capacitor. The most popular form is magnetic coupling. ( I am not now referring to the Berning ZOTL RF power conversion output stage because it is patented and not relevant to this discussion)
Now lets get on our Vespas and talk a long ride back, back, back so we can get an overview of what has been happening over the last three years....(1) a new supply of better directly heated triodes that are affordable have made it possible for Mr. Bud to join the DHT tribe...Gadzooks affordable 300Bs are everywhere (2) there has been enormous creativity in single-ended circiuit design stimulated by Japan (3) a new generation of magnetics has appeared in both output, interstage, input and line stage transformers. These are three elements which have been the foundation of the DHT revolution..choices, choice, choices...Freedom of Expression. God Bless America.
Because YOU can not make your own tubes or wind your own transformeers you concentrate, rightly so, on developing the most refined circuits, so what we find on the world wide web is a very deep discussions of the smallest details of circuit design. What could be more stimulating than a debate about input circuits and bias configuration? No group is more intense in this investigation of the aesethetics of circuit topology than the SET DHT tribe, and that is apparent to all surfers of web sites devoted to this subject.
WHAT GOOD IS YING AND WITHOUT YANG?????
I would like you all to go back and re-read Scott Frankland article about SET/OPT Speaker interface because, from my point of view, it shouts You can not separate YING from YANG, because it is impossible to separate your SET OPT from your speakers magnet structure. Let me say that another way:
Output transformer magnetics and can not be separated from speaker magnets. When we only discuss the subtlies of amplifier circuits we are in denial because it is impossible to refine an amplifier circuit out of context to the magnet structure of our speaker. The magnetics of our tube amplifiers output stage CAN NOT be separated from the magnetics of our speakers...they are one integrating/interacting magnetic circuit. That is the point of Scotts article and he is right, and he is right that we are avoiding this intrinsic connection, and for a good reason....we have too few choices America about speaker magnetics.
Pardon me for one second I have to change costumes and put on my RED HOT CHILLI PEPPER UP YOUR BUTT costume.
Consider this: 80% of the cost of speakers is the cabinet and finishing. Even the best speaker companies, in spite of their claims, are using cheap ferrite magnet drivers, because American audiomaniacs are easily victimized, and the audio press is terrified of discussing this issue for fear of scaring away their advertisers.
I was having lunch with a speaker designer the other day and we talking about this subject and he asked me if I thought consumers would be willing to pay the extra $100-$500 for much better speaker magnets. Give me a break. Think about this: Mr. Serious Audiomaniac spends thousands of dollars on state of the art equipment and the signal generated by this equipment winds up in a $75 ferite magnet driver in a $10K speaker! Or think about your $300-$600 magnetic output transformer being connected to $50 magnetic speaker driver! Does this make sense to you? Not only does this not make sense, it is exactly the opposite sense that we find with Japanese audiomaniacs, who is into TRIODE MAGNETIC WHOLEOSITY.
Japanese audiomaniacs spend as much time contemplating their speaker magnetics as they do their output and interstage transformer magnetcs because they are into the wholeosity of their magnetcs. They are right!
The next stage of the American audio revolution will be a much more serious consideration of the wholeosity of magnetics, the YING/YANG, the completely inseparable nature of OPTS magnetics and and speaker magnetics.
How easy is it for speaker manufactures to start using better quality magnets? It is a no-brainer, but they wont until YOU start demanding them.
THE OPT REVOLUTION
Lets look at our choices: We can choose from the Japanese Masters, who make very expensive objet dart. We can savor the aroma of the Italian Masters. We have enormous creativity in America that ranges from amazing value at $100 from Hammond, to MagneQuests new/old Parafeed, to the new Plitron torroid SET OPTs, to Jack Elianos classics. There are the Ludahls of Sweden and the Sowthers from England. Every year our choices expand. This is beginning to become a very heavy subject, which is why I created this separate category on the Triode Guild web site.
We have gotten so small on this subject that we are debating the aesethetics of variouis laminates, winding techniques, cut-cores, torroids, permalloy, silver wire vs. copper, gapping techniques.... buzz words galore.
My rantings about the need for power supply stiffness can now be connected to the stability of the magnetic field in an OPT, and how the harmonics of our power supplies are affecting the resonate character of the OPT. Your power supply is the electrical source for the magnetic field in your OPT, and the quality and stability of that magnetic field is the foundation of all your design work; all that your audio circuitry is doing is amplifying/modulating that magnetic field!
COMING OUT OF THE CLOSET WITH BACK EMF
No one likes to talk about this subject: A loudspeaker is not only producing a music signal but is also generating a signal (a loudspeaker is a microphone) from the sound reflected in the room and it going back into the speaker (back electro-magnetic force), and this signal is modifying the electrical field in our output transformer as form of distortion. ( Heres a simple demonstration: connect a scope to the B+ rails of your amplifier while it is connected to your speaker and not plaing music and then play music with a another source and watch what happens to the B+). The nature of this Back EMF distortion is dependent on the room acoustics, the music we are playing, the design of the OPT and our power supply ( all of this boltsers my case for high effeciency loudspeakers). Back EMF is a form of universal undesirable feedback/distortion, and may explain why small cone speakers have such midrange virtues.
THE EXPANDED AURAL MATRIX© and OPT DESIGN
As you know I have been writing about the very different aural matrix created by single-ended and push/pull circuits, and I have noted the quality of the aural matrix created by the Sun Audio amplifier.
I am now in the middle of testing a wide variety of single-ended OPTs and (obviously) when connected to the right speaker magnetics these different brands and types of OPTs create very different aural matrixes. This means that you may have to increase the frequency of your electric shock treatments because give the wide variety of 300Bs and 2A3s we could spend days, weeks and years, exploring all of the different artistic possibilities...and that is what this audio revolution is all about...having choices so we can decide what is right for us.
The articles that follow will be a further exploration of the magnetic revolution and I hope transformer artisans will contribute to this exploration. Lets burn up the Triode Guild chat room on this subject.