Tubes vs Solid State - Imaging, Soundstaging, 3D

I'll respectfully disagree with Mapman 's assertion that modern implementation of NFB has been improved. When I hear amplifiers that utilize generous levels of NFB it's very apparent in that there's an artificial character quality of the sound. I just don't hear the same naturalness or realism of instruments and human voice. Simple tube circuits that omit or use minimal NFB are much better sounding and more convincing of reality.

I recognize that this is just my observation based on listening to many different amplifiers over the years. Mapman I certainly appreciate your satisfaction with your current class D amplifier and congratulations on your happiness with them. I acknowledge that we just hear things differently and may in addition have very dissimilar listening priorities.
I haven't come across a SS or class D amp that can approach what the well implemented no NFB tube power amps are capable of. For sure I'm in a minority as there are far more owners of SS amps compared to tube.
Charles,

Hi Charles,

No need to agree, but I suspect its a stretch to think that while technology has progressed in most every way greatly over the last 40-50 years, amplifier design has remained stagnant.

Whether or not a good modern CLass D amp with NF sounds as good as a tube amp or not is a different story.

I'd agree that they are not likely to sound the same, and each is likely to perform best in a completely unique and different system.

I've used many a good sounding "high end" system for reference in putting my own together, including many very good tube amp based systems.

I could likely not afford the tube amp I would need to drive my preferred speakers the OHM F5s to their max, nor the power bills that woudl come with it.

So my case is somewhat unique in that the OHMs are a somewhat unique design and case to optimize. The Class D amps do it though and in manner that brings the best of both worlds to the table in a way that works for me.

If I had the time, money and patience to deal with the tube amp I would need for similar performance with these speakers in particular, I would be tempted, but that is an alternate reality for me.

No one amp, speaker or anything holds all the cards. Each has different strengths or weaknesses. You can compare any particular aspect of design or sound you want, but its just a small part or the total story.

Just saying. ITs fun to gab about such things I think.....

Sometimes, I feel like A Poor Misguided Fool.

Another musical interlude....

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,