Tubes vs Solid State - Imaging, Soundstaging, 3D

So hearing hiss is better than not hearing harmonics that can't be heard? I must be missing something?

Correct- you are missing something. The hiss which is the noise floor of a zero feedback circuit is at a low level, just as the noise floor of an amplifier with feedback is at a low level. The point is that the noise floor of a circuit with natural hiss will seem to have more detail, as our ears can hear information below then noise floor; in a circuit with feedback they can't.

Regarding your other comments re class D and tubes... you could get a tube amp to drive your speakers- you might want to use a set of ZEROs. Worth a try if you ever consider it. IMO Class D is a technology that may well prove to be superior. The answer is told by price/performance curves and the question is where is class D on its curve? If somewhere in the middle it may yet surpass existing technologies.

Since Transistors and Tubes are both mature technologies and Transistors being arrived at a lower performance level than Tubes, the fact is that our grandchildren will be arguing over the differences. But what this also means is that class D will overtake Transistors before it can overtake tubes. In some cases we have already seen this, so the theory is being proven in practice.

Put another way, will class D then overtake tubes?? That remains unknown at this time. What we *do* know is that it has not done so yet.

I maintain that you don't have to know anything about technology to understand that tubes are in fact superior. The simple fact is that at this time, tubes have been obsolete for longer than they were the only game in town! Think about that. Normally when a succeeding art appears, it supplants the prior art easily and there is not much looking back- the prior art becomes a cottage industry at best; cars and horse-drawn buggies are a good example.

But tubes are still vibrant- the market somehow continues to demand them half a century on after their declared 'obsolescence' (there are more manufacturers of tube gear in the US now than there was in 1958...). That's really all you need to know- if the succeeding art were really better, tubes would be long gone. You don't see them in TVs anymore and they've not been there for a long time. That says that tubes don't work as well as transistors in TVs- or computers! But they seem to do just fine in audio, and new types (KT150 being one of the latest) are being introduced. That's not a description of a technology that is obsolete.

Hi Mapman,
I have no doubt that the Bel Canto is a quite fine solution that fits your needs and I meant no criticism in any way. Ralph made certain points about the effects and consequences NFB that ring true in my listening endeavors and so it caught my attention. I of course agree with you in that there's inherent compromise with any amplifier choice. For what I seek and place the highest priority on, the simpler lower power amps minus the NFB get me the closest to that sound.
Charles,

My guess is Class D still has upside, but is pretty darn good already. I'm finding it better already than most Class A/B transistor amps. Class A/B/D all use transistors, right?

Tubes are not obsolete. They have unique charms. Definitely a small niche in the big picture though. Bigger in high end audio no doubt. That may not change.

High end audio will always have a special place for the other wise unconventional where it can exert some control in unique ways over the market.

The bigger question is does high end audio as it is comprised today grow or shrink over time as new innovations come about? Being stuck in the past is often not a good formula for growth.

Class D is a game changer IMHO. Tubes beware!

Charles,

I was looking at your system in conjunction with formulating my response.

No doubt, you have a well thought out setup with some very unique qualities as well and a lot of care has gone into it.

I have only gotten to the point in recent years where I am able to listen for hours on end given the opportunity and be continuously sucked further into the music.

I have a wife and kids, a house and jog and other hobbies as well, so you know how that goes. ALways something to do. All else aside, I can be quite happy just sitting and listening.

But there are so many ways to skin the cat. I hear great sounding stereos all the time now at shows, dealers, plus more good sound at live events when I get a chance. Tubes are often part of the equation, possibly a necessary ingredient still somewhere, just not in the power amp in my particular case.

The thing is there is so many ways to skin the cat and get good results. The common ingredient seems to be a love of music and a desire to get things just right in order to maximize the experience while it lasts. And maybe a tube or two or more can't hurt.

"The point is that the noise floor of a circuit with natural hiss will seem to have more detail, as our ears can hear information below then noise floor; in a circuit with feedback they can't"

Assuming the noise floor is low and can't be heard anyhow, what is there to hear below it?