It is early morning, and you can smell it and hear it before you see it. Your body begins to ache and quake as you approach. You know it just beyond the bushes, and your face can begin to sense the mist that it is covering it. Now there is an intensity of bugs and flies. The ground becomes soggy and soft. As you get nearer your thighs can feel it tugging. You push the bushes apart and there it is before you....a perfect trout stream. Not to wide, not too fast. It is a classic with trees drooping over the bank, with birds darting over it, back and forth, lunging and twist for the rising flies. The morning light reflects off the water but you can see the dark areas, the deeper pools, among the glowing brown glistening rocks. Today is going to be a good day. It is an Ernest Hemingway day.

There is in the soul of many men a perfect classic trout stream. For some men it is big and roaring, like the Snake River in Idaho. Some have gone to trout stream heaven in the mountains, but for me, the perfect classic trout stream has certain proportions; those dimension that invite an intimate exploration. Knee deep or up to my ankles or just above my waits, this stream doesn’t over power me, but embraces me. I can become one with it. Out West, on the other hand, you move quickly up and down the stream covering lots of territory and make big casts over long distances. I prefer the challenge of a perfectly placed fly by a log, under a tree, where a brown trout whose is a professor at Harvard, may be feeding. Much of the joy of such a stream is just sitting on the bank and watching it be just a perfect trout stream, with millions of years of wisdom gliding under its shine.

Such a stream demands and deserves a fly rod perfectly designed for exploring its mystery. It can’t be too powerful or it will be impossible to gently lay those very small flies in a natural way, in exactly the right spot. No, such a stream requires an instrument of supreme finesse and delicacy.

In 1962, while I was a sophomore in college, I met my perfect flyrod. I dreamed about this fly rod in high school. It was the favorite fly rod of Lee Wulfe, the famous trout fisherman. It was my dream, and I have used this dream since that time. It is an Orvis, Ultra-Light 7 foot flyrod and it is made from tonkin cane bamboo that has been impregnated with resin. I bought it used for $75, and if I were to buy a new one today it would cost $1,500, and I am taking it with me into the next life time.

The fact that it is made from fine slivers of bamboo and is not a modern fiber glass, or graphite fishing rod is important, because, like directly heated triodes, bamboo has a distinctly different feeling than rods made from synthetic materials. Isaac Walton, and Ernest Hemingway used a bamboo fly rod and that matters to me. There is no language that accurately describes the delicacy and grace of a fine bamboo fly rod. It is also obvious to me that streams and trout prefer bamboo flyrods. Many a trout has told me that they felt dignified by being caught with a bamboo flyrod.

Which brings me to the 2A3 directly heated triode, and especially the KR 2A3, and especially the KR 2A3 in David Berning ZOTL SET. I have been receiving many inquiries about the 2A3 tube. "How does this tube compare to the 300B?", "What do you think of the 2A3 Sun amps", etc, etc. I have only two long term direct experiences with 2A3, and that is with the Welborne SET, and the Berning SET/ZOTL bisexual, and in both cases I only used the KR 2A3. I have had a very brief experience with the VAIC 2A3, which I hope will become available.

My experience with the Berning ZOTL has been revelatory because it is the only amp in the world where you can, wham, bam, thank you mam, switch from 2A3s to 300Bs, with absolutely no adjustments necessary. In this single case I am comparing the tubes in exactly the same circuit.


As I have said so many times before the Berning circuit is too is direct coupled from input to output, and what ever smegma is in the audio circuit or input because radically apparent. I began to detect a strangosity in the KR 300Bs while listening to them in the ZOTL that was not apparent in either the Sun or my own custom/Plitron torroid OPT SET amps. Both of these transformer coupled amplifiers did not have a circuit tizziness with the KR 300Bs that I heard with the ZOTL, They were filtering out high frequency microphonics that ZOTL was letting through.

This seemed to be small price to pay for all of the advantages of ZOTL, until I started to listen to the KR 2A3, which did not have those high frequency microphonics. These tubes, like my delicate flyrod, have a grace and finesse that begins to grow on your, and in time I began to spend more and more time listening to them.

Yes, it is true that all of the KR tubes have a tonal family resemblance, but the 2A3 is more subtle and graceful; it sounds like it has matured, in the way great old violins or guitars mature in tone.

Because 99% of my listening doesn’t require more than about one or two watts power is not the consideration, but when I want to get down the limitations of the 2A3 relative to the 300B become poops out, and doesn’t have the bass slaminess that I love when I rock.

If I can return to my original analogy: the KR 300B is a modern high powered graphite fly rod, the 2A3 is bamboo, and for certain music nothing is better.

Which brings me back to the one way, which is the way that all trout stream flow. The KR2A3 is still an unexplored gem. This tube definitely deserves major experimentation with driver stages. It demands the best tube regulated power supplies and refined output transformers. The Lowther cult has had the dreams answered. I wonder what this tube sounds like running at about 300 volts in a super deluxe transformer coupled circuit, which makes me, like you, wonder about the Sun push/pull 2A3.

If David Berning wants my left arm, he would design a bi-sexual push/pull 2A3/300B ZOTL circuit, so we could have the best of all worlds.

Also, just discovered from Ron Welborne that Count Kron has done more development work on the KR 300B and it is more refined! I wanted if it is an improvement, or just different. I will post my full report when I test them.

As more and more of our brothers are seeking the mystery of the music shadows that can only be found lurking under the drooping trees, new tubes are appearing that gracefully cast out our souls.



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