300b lovers

Hi Lynn and Don,

It is very interesting to hear more details about IT versus LC coupling between 6sn7 and 6v6. What is a difference in sound?

Umm, hard to describe. More "there" there. More sense of a physical presence, and a better feel of the performer’s musical intentions. More hall sound. Most of all, a feeling of the performer being in the room instead of somewhere "out there".

Not the usual audiophile verbiage, but it’s immediately evident when you hear it.

By now, the Blackbird is very close to the original Karna, but with greatly improved power supplies and a much more practical monoblock construction, which also improves performance. Full credit to Don for pulling off what I thought was impossible.

As you approach the highest levels of audio, the sound kind of takes a right-angle turn from the usual path of improvement. Instead of just getting more and more clear and vivid, suddenly, there’s a physical sense of musicians being right there in the room, instead of sounding like a very good recording. The instruments have physical size and feel like you can reach out and touch them.

A piano sounds like it’s five feet away, and it sounds BIG. Even "bad" recordings sound like this. Is something being added? No, I don’t think so. Instead, a mechanical quality is no longer there.

This phenomenon is well known amongst triode practitioners. It’s not a secret. Unfortunately, it is almost never heard at hifi shows, so don’t expect it there. I’ve heard it several times at the advanced DIY level. Never heard before from any mainstream or transistor system, which is why I started working with direct-heated triodes in the early Nineties, after hearing and reviewing the Audio Note Ongaku and the Herb Reichert Silver 300B.

These are the kind of conversations I used to have with Harvey Rosenberg, who definitely "got it". Unless you knew him, you didn’t realize his clowning around, and occasional jaunts into speculative metaphysics, was an act designed to chase away mainstream audiophiles (which it did). Of course, I can speculate about metaphysics for hours on end, as folks who met me at the PAF discovered. But the clown act was pure Harvey ... I’m too sobersided to joke around like that. But we did discuss the subtler aspects of musical perception, and how they interacted with culture and worldview.

I am not sure where capacitor coloration comes from, or what’s causing the hours-long "burn-in" process. It can’t be measured, and the plausible mechanisms are pure guesswork. But it’s there. In a positive sense, direct-heated triodes, in the right circuit, have very special qualities.

Not everything is revealed by the spectrum analyzer, and the usual audiophile lingo falls short of describing what triodes really sound like. Sanskrit or Japanese might be better, but I don’t speak either, although I am conversant with a few basic Zen, Taoist, or Vedanta concepts. English is not particularly good at discussing subtle aspects of perception and consciousness.

Now that Don has built a version with zero coupling caps, he’s having the same experience I had when I first heard the Amity in 1996. The Karna was a development of that, and the Blackbird is a development of the Karna.

Basically what Lynn just said.  Once you hear it you cannot go back.  Even the best caps cannot touch it.  Now, that said, you will not hear this if the rest of your system is not up to the task.  You put a $500 DAC in front and a mediocre preamp that uses small signal tubes, and a mediocre pair of speakers behind and you will mask all of this.  You are not going to get this with cheapo ITs either.   The Lundahls I played around with last year sounded good, but rang at 15KHz.  That doesn't mean Lundahls are bad, just that they were not designed specifically for this circuit.  So if you get really good quality ITs that are designed for your circuit, then you will hear what Lynn described.  These replaced VCap ODAM, and I also tried top shelf Miflex and Duelund JDM copper foils.  All are very good caps.  None has the realism of the custom wound Cinemag transformer.  I have no doubt the Monolith iron is superb and I am about to try their OPTs whenever they arrive.   But you need iron of this quality.  You wouldn't judge all coupling caps based on a cheapo Solen, nor would you judge all ITs based on something like a Hammond or Edcor.

There are levels and to my ear in our circuit (important caveats), the top quality IT is better than the top quality coupling cap used in the LC with a very good anode choke.   My 2 cents and feel free to disagree, but it is what I hear.

What you will hear in your circuit .... I don't know, and it doesn't make me right and you wrong or vice versa.

Agree 100%. Don is describing what I hear.

The metaphysics are optional, but they have a good toolkit for describing perception.