The night was stormy. As my coach struggled up the mountain, its four horses screamed as lightening crashed above us. Hour upon hour we struggled up and up, terrified that rocks would come crashing down on us. I could hear the howling of wolves following our coach. The sun began to rise, the mist cleared  and I could see off in the distance at the very top of the mountain, a forbidding 14th century stone castle, now the home of the much feared Count Kron.

On assignment from Positive Feedback I had traveled across heaving oceans by schooner, across national boundaries and finally up this black glistening stone mountain in Czechoslovakia to interview the mad scientist of thermionics in his very secret laboratory that was producing terrifying tubes.

To protect me Fritz, the Audiomaniac Vampire, who still has relatives living in Transylvania, gave me a heavy duty silver cross to wear, had filled all of my pockets with garlic cloves, and had even given me his custom made garlic mouth wash, But I was still frightened. Fritz even called his close fiend, Count Dracula Jr. ( grandson of Count Dracula who is now into punk/heavy metal), to do a background check on Count Kron. Were the rumors about Count Kron true? Had he really invented a new form of life that threatened to dominate the audio industry?

With a creaking sound the giant black iron gate opened and a hunchback audiomaniac with one red drooping eyeball beckoned me, in to a dark hall with just a few candles burning...a dank musky odor of rotting decaying dead transistors filled the hall. The hunchback did not speak but I followed him. He dragged his foot and lead me to a spiral stair case that was leading down, down, way heart was beating very fast and I reached up to my neck and made sure that my silver cross was still there, and then I reached into my pocket to make sure that my garlic was loaded. Would I ever get home alive?



Everyone knows the story of Dr. Frankenstein and his desire to create a superior human being. I love this story because there is something in our DNA that compels...”I can do it better”. If that weren’t true we would all still be sitting in caves, and NOT in our living rooms listening to directly heated triodes.

Dr. Riccardo Kron is a mad scientist, which is a good thing,  because in his artistic arrogance he believes he can take normal forms of life and make them superior, which is exactly the way Beethoven, Michaelangelo, Elvis and Ford felt. We can not separate vanity from the artist and that is a good thing. And let me remind you that many men have assaulted the perimeters, attempting to push the boundaries of the audio arts and have failed. Those who succeed are our heroes and become immortal. Count Kron is on this path of immortality.

Count Kron is a typical revolutionary character...created by the revolution, and then becoming its guiding force. Kron didn’t turn on the switch that began the world-wide directly heated triode revolution, but once the world wide lamp was on, he seized the opportunity and is now creating the new high ground for us to ascend.

If you can dally with my dialectical thinking....on one end of the dialectic we have the Sovtek 300Bs, making it possible for the bourgeoisie, like you and me,  to participate in the revolution, and on the other end of the dialectic with have the KR tubes, providing us the dream of heavenly ascension. It is beautiful thing this revolution, because it expresses simultaneously our craving for bread and eternity. There is an inevitability to this ascension because I believe that directly heated triodes are better than sex, and very much like it...once you have lost your virginity with Sovtek 300Bs you will start climbing towards more subtle and dynamic forms of musical eroticism, and for that type of spiritual development you will eventually need KR tubes.



As you know I am fluent in the universal language of the thermionic techno-shaman, and it doesn’t matter if he is speaking in French, Italian, German or Japanese....the language of schematic says it all. I suggested to Count Kron that his new tubes demanded more..that they needed more advanced drive circuits, better power supplies and the best output transformers. He agreed that the highest quality output transformers were necessary, but he was only referring to single-ended types. The Count didn’t know that I had a very serious conversation with Nobu Shishido, while he was alive (it is harder talking to dead people about tube circuits) and Nobu was very assertive that the Kron tubes needed an interstage transformer to drive them properly. Then I noticed in Costruire, the Italian audio magazine, all of the SET circuits using KR tubes also was using a “power tube” as a driver circuit.

So it occurred to me that Count Kron was being kind and doesn’t want to come out an assert just how good and demanding his tube really are, which is probably the right thing to do. Why would he want to insult anyone?

What am I saying? It is very obvious to me that to fully realize the expanded possibilities of the KR tubes better drive circuits than our conventional RC coupled 6SN7 are needed, the best output transformers must be used, and much stiffer and lower impedance power supplies must be employed, and I am also suggesting these tubes demand absolutely the finest speakers.

But let me go further with my discoveries and the Count’s modesty.

I was so impressed by the KT 300BXL in the Sun Audio of Japan’s SV 300 MkII 300B push/pull amplifier ,with Tamura transformer phase splitter, (read all about it in the Fall issue of PF)  that I was compelled to connect my tube regulated power supplies to each mono chassis, and I was taken by surprise. We are not talking about an incremental advancement in the aural matrix here...and the stock Sun power supplies are no slouches either, being superior to what you get in America. Something alchemic was happening...the combination of the highest quality Japanese output transformers, the transformer phase splitter, the KR tubes and the heavy duty tube regulated power supplies released a hidden quality inherent the KR tubes...confirming my suspicions about Count Kron’s will take years for American tube amplifier  designers to catch up with him. This combination is making me into a heretic...I am falling madly in love with push/pull amplifiers again...of the Japanese type. You will have to wait for the fall issue of PF to read my full report on the Sun amplifier

I don’t think Count Kron has ever heard his new tubes in such a refined push/pull amplifier configuration, and  I have suggested that he contact Sun Audio directly to explore a joint venture.  In his notes to me the Count, like all SET lovers, asserts that the push/pull thing is crude, but he is only right because he has not heard the genius of Mr. Uchida’s Sun amps. I am asserting that the blending of Count Kron’s and Mr. Uchida’s genius could produce a extremely powerful new paradigm of ultra-refined push/pull amplifiers that would satisfy America’s need for refined (not pentode) power.

 I am also certain that Count Kron has never experienced his tube art in the David Berning SET ZOTL....which quite frankly I don’t like (joke)...because it is too revealing, too lucid and too merciless in its revelations of the insidious flaws in my (and every audio system)...I don’t know if I can handle that much naked truth....maybe I too am not ready for this leap forward in triode truth....on the other hand....

In the ZOTL circuit which has no output transformer, is directly coupled and has regulated power supplies the low frequency genius of the KT 300B is apparent, and this quality  can not be experienced with any single-ended output transformer of any kind.   When we usually talk about 300Bs we are talking about midrange glory, and this is completely determined by the limitation of single-ended output transformers. In both the ZOTL and Sun circuit we can experience a quality that is never ascribed to 300Bs...totally testicular bassosity with a degree of aplomb that I have never heard in a pentode amplifier. The KR tubes has a dynamic capability that causes us to conclude that they have twice the power of normal 300Bs.



Before I begin this section let me remind you all that I am short, bald, my mother never loved me and I am very neurotic and hypnotic, so because of these childhood traumas the Lord in Her Infinite Wisdom chose to compensate me for these great Karmic injustices by giving me the passion and skills to shred the perimeter of the audio arts...proving that there is divine justice in the audio arts...if you work for it.

So it is once again time to kick sand in the face of all of those audio Nancy boys, who think they can reach the Nth Dimension of HyperSpace with “normal” store bought audio gear...not possible.

EXAMPLE ONE: What I have created in my home is completely unique because it is a blend of two very different revolutionary forms of audio circuits...the Sun Audio push/pull 300B amps on the woofers with the Berning ZOTL SET 300B on the tweeter,   all of which use KR 300B tubes...the Sun amps are connected to humongous tube regulated power supplies, and the Marchand tube crossover is doing its other words there is nothing in between the output stages of these amps and the drivers, so I can experience the full measure of Count Kron’s thermionic coolosity...and what is the message?

If you have sex using a heavy duty rubber condom something is my metaphor. Which brings me back over and over again to the same is not possible to fully appreciate KR tube’s unique qualities when they are used with current “normal” tube circuitry and speakers. Experiencing these tubes completely unfettered is a totally unique I boring you with my repetition?

EXAMPLE TWO: These KR tubes are such a compelling experience that I rebuilt my own custom 300B SETs...the ones with the MagneQuest output transformers. I refined the drive circuit, and most importantly there is now a connector so I can connect the front end to its own independent regulated tube power supply thereby totally isolating the front end from the output stage which runs on its own tube regulated power supply. As far as I know this is the first time I have encountered anyone trying this experiment, for which it took about twenty minutes to do the wiring. (This historic no-brainer experiment was done for you the gifted listeners of America...and remember vote for me).  Each output stage is connected to a Kepco power supply that uses five Svetlana 6550s which means I am using ten 6550s to regulate the B+ rails for the KR tubes...and they deserve it. (Secret: I can change the texture of the KT cream by adjusting the voltage of the output stage, and because I need so little power I usually listen at the very creamiest point in my system....348 Volts...for more guts I wind it up to 425 volts!) What did I discover?

It confirmed my belief that to fully realize the potential of these tubes the most sophisticated power supplies are needed. With the total electrical isolation of the front end I gain a quantum leap of delicacy and refinement...meaning clarity and harmonic piety that did not exist when the amplifier had, as is the typical case of all SET,  one B+ rail....... which is never actively regulated.

I also confirmed that it takes the best vintage NOS 6SN7 of the RCA type to experience the dynamic...wide..deep...aural matrix of these tubes.

EXAMPLE THREE: When I installed the KR 300BXL in the Golden Tube $1750 Stereo 300B amplifier there was a comparable transformation, proving that at all levels of sophistication the KR advantage is apparent.

SPECULATION: Dan Schmalle, John Camille and Mike LeFevre have been conspiring on a new single-ended paradigm, with the KR tubes, that includes a trick input stage, parafeed output stage and other trick stuff....all designed to  exploit the unique capabilities of these tubes. I will report as soon as I audition their new art.

WARNING:  Anyone who uses these tubes and complains about a lack of midrange refinement or turgid lower midrange is really complaining about their power supply fog.

Am I causing you pain, aggravation and suffering? I hope so, because that is my job. Remember all of the pain and suffering that Michaelangelo endured painting the Sistine Chapel? And that is the difference between you and an audio Nancy are can take the cold hard truth.

Shall I say that another way....when you drop a high performance engine in your car make sure you have the complimentary carburetion, ignition and exhaust system or you will not realize its full potential.



Are those Mercedes-Benz labeled motors in those Formula One cars really a Mercedes-Benz motor? The current generation of KR tubes is a result of a number of years of refinement. I have a pair of earlier KR 300B tubes, and the current KR 300BXL is much more refined as are all of the new KR tubes.

This new KR 300BXL is all about the art of cunning. Count Kron puts the number 300 on the tube. Yes,  you can plug it into a 300B circuit, and you should probably have adjustable bias. And yes it does sound like a 300B,  but it is genetically a completely different tube. The Western Electric 300B is the classic 300B and all other “normal” 300Bs should be judged against it. The KR 300B is in a completely different class. The Western Electric 300B is a 1956 Harley-Davidson Electro Glide, the KR tube is a nitro-burning supercharged Harley Dragster...if you get my meaning. You know they both sound like Harleys, KR is much more, yet none of the magic or delicacy of the classic 300B midrange is is just fuller, more passionate and dynamic....and upsetting.

The physical and electrical design of the KR tube is very different than the classic WE 300B, and that is in every construction detail from the glass bulb to the construction of its “guts” to the vacuum to the gold plated pins. When you compare the two tubes these differences are apparent. The KT 300B is a heavy weight tube compared the normal 300B and the weight of the glass may be related to the fact that the KR tubes have a much higher vacuum. The KR tubes are manufactured within the Tesla tube manufacturing facility in Czechoslovakia so Count Kron is taking advantage of a very sophisticated manufacturing facility.

The technology he developed to make his tube is significant, and his claims about his tubes have an extraordinary high level of vacuum are difficult to prove because how do we measure it without breaking the tube, but then the vacuum has disappeared. If his claims are true then this is a big breakthrough in tube design because the quality of the vacuum within the tube is a major elements of its quality. The proof is in the listening and Count Kron must be doing something right.

In every amplifier I installed the KR 300 BXL  the same effect was experienced...they transformed every amplifier into what seemed like each had doubled its dynamic power, expanded its frequency range, broadened and made deeper its aural matrix and created a richer and more complex harmonic continuum. Because of the extended low frequency capability of this tube, there is an enhanced tone that is richer, warmer and creamier. And once again let me remind you that I have experienced the upper frequencies of these tubes in a unique way because of the Berning ZOTL amp which has no inductance in its output stage, and because of the Sun Audio amps have much better high frequency response than all of my stock and custom SETs.

All of these virtues were also apparent with my “normal” reference speaker, a pair of  86 db efficient B&W ($1,100 per pair) CDM1 minimonitors. This leads me to suggest that the KR 300s will supercharge a “normal” 300B SET when used with a “normal” speaker......but I remind you of my caveat...most of my listening is with 99 db efficient alnico horns, and while I am able to achieve full knowledge of this tube’s virtues, I am only using a tiny fraction of its power, and in less efficient monkey coffins you may not be able to appreciate its full dynamic glory...and I am certain that you do not yet have an amplifier that can showcase its full  genius...but let me assure you again, and again, and again, that the limitations of what you experience is not due to the KR tube, but to the design of your amp and speakers.


There can be no refutation that there are many very serious thermionic techno shamans with very refined taste in  triode cream who prefer the lighter more delicate flavor of 2A3s and this especially true for Japan and Italy, where we can find, believe it or not...scorn...for the 300B. I may be the only person who truly understands this universal macho hierarchical hyper-horse shit flinging which is required to stay at the top of triode totem...because I practice it, like everyone else. So 2A3s are way cool, and very soon in America you will be sliding downward if you don’t have a 2A3 amp in your arsenal, which explains why my gun cabinet is filled with a broad range of calibers from the .22 Hornet to .458 Winchester

I am fortunate to have Ron Welborne’s Moondog 2A3 mono amps in my listening room,   which are a perfect showcase for this new KR tube which produces a positively erotic form of cream which is lighter than the KR 300B know it is like having sex with a ballerina.  You might say that the KR2A3 cream is a type of cream that Angel make when they cream over their favorite jazz group.

This tube has a midrange and upper harmonic elegance that most 300B tubes can never achieve, and you would right to say it is less coarse and more transparent, but it also doesn’t have the ability to project the type of dynamic wavefront and power that the KR 300 projects. But we are comparing two different types of cream here, and this is not and either or is about enjoying both for their unique flavor.

This tube is the darling of the Lowther/no crossover cult and it is understandable for those who die for midrange cream, and are prepared to sacrifice everything else...this is the tube.

I have been exploring this tube’s 3.5 watts of magic with the Tannoy horns and it produces more than enough power to blast my room, but it is with voice and chamber music that its magic overflows. Here we have the musical intimacy that 2A3s are known for, and explains why some of the vintage NOS 2A3s sell at such outrageous prices.  According to the 2A3 masters, I have spoken to, this new KR tube is up their with the best of the classics and may be better in some regards. Don Garber thinks he may be able to get five watts out of this tube!

Like the KT 300BXL this tube is a true work of art, and comparing it to other 2A3s makes it apparent that this is something quite special.

This tube is not to be confused with Chinese manufactured tubes and is not meant to be a less expensive 300B...this KR tube is the newest most refined medium weight triode cream, and also demands comparable refinement in circuits and speakers.

My experience using this tube naturally compels me to ask...what would this tube sound like in the Sun Audio push/pull 2A3 amp or in a Berning ZOTL SET? That is a dream for another time.

Besides filling a need in the marketplace for a high quality new 2A3 I think Count Kron was also proving to his critics that he was not just the master of the supercharged high powered directly heated triode, but could also create a triode of unparalleled refinement, and he has accomplished his goal.

In my desire to finish this article I have not had enough time to experiment with this new tube but watch my web site for updates.

For those who have never experienced 2A3 cream here is a suggestion: fill your bath tub with medium weight whipping cream and then get in it with a very large straw with a pair of swimming fins on. Play Puff Daddy’s music track for Godzilla while you thrash in the cream with your fins, until you notice the cream starts to get thicker. While you are thrashing in the cream suck some of the cream.


Give me a break, and give me some time, and I will continue my shredding of the perimeter. I am really loooking forward to the KR rectifier tube which could be a big step forward in power supply improvement. And of course those higher powered KR tubes in extremely refined push/pull amplifiers is probably exactly what is needed to satisfy those who need between 30-75 watts of refined power.


I trying to convince Ron Welborne to create his next “new and improved” 300B kit which will have some new circuitry, advanced power supply design and be able to show off the capability of the KR 300BXL.


What does this all mean? If you buy KR tubes you can be certain that you have probably purchased a rare piece of audio that will not become obsolete in the next ten years.

Let me say this again another way....Count Kron’s tubes are so advanced in their aptitude that I believe it will take years for America’s tube amp designers to exploit their limits. And tragically I don't know any available store bought speakers that will reveal their unique qualities. Am I kicking sand in their face? Absolutely!

Believe me I can understand how upsetting this is, and unfortunately that is the price we pay for reaching a new plateau of possibilities in the thermionic arts...made possible by fearsome Count Kron.



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