Tubes vs. solid state.

Amazing and very interesting discussion. Please keep in mind that there are several lines of thought regarding amplifier design. 1) the amplifier is designed to drive specific loads, 2) look like an open circuit (impedance wise) so that it does not load down other electronics feeding it or 3) is specifically designed to accurately reproduce and amplify the input signal. If you design an amplifier to accurately reproduce and amplify the input signal without taking into account what loads it must drive, it will oscillate, blow up or just not work correctly. There is a difficult engineering dance that engineers must adhere to in amplifier design and also, compromises that must be taken in any amplifier design. The point that I was trying to make earlier and in other posts is that one must know what instruments and vocals really sound like first in order to understand if the equipment is designed correctly and working correctly. If it sounds as if you are listening to speakers, then, something is wrong. If you can't tell where the artist are on the stage, how deep the stage is etc. then either something is wrong or the music was recorded badly and maybe there wasn't a stage at all or instruments, but electronic instruments only. You never know what was recorded and how. It is hard to judge. I am not an advocate of classical, live unamplified, amplified, jazz, rock, etc. I love any music that is good. However, understand that most kids have no clue that they are listening to drum machines, electronic instruments instead of real instruments, etc. So, when they hear your system, they may not appreciate it because they have a bad point of reference to begin with. A short story. years ago, I took my daughter to a concert to hear (see) Roberta Flack. Outstanding in person, recordings, don't sound nearly as good as live. you could hear deep sighs and breaths and gasps from the crowd as she played piano and sang. That is when my yound daughter learned what signing really was. Remember, we are constantly trying to reproduce something that was recorded. 1) was the recording done correctly? 2) the mixing? 3) was the replay equipment and cables designed and build correctly? All of these inpact the ultimate sound. Did the artist step out of your speakers and can you see the room, instruments and maybe her face? if so, you are there. If not, then we aren't there yet. But, you got to admit, it is fun getting there.

Enjoy

Minorl, sounds to me as if you are saying something that I've been harping on a lot- that the playback system has to take into account the rules of human hearing/perception and obey those rules. Designing to specs on a piece of paper doesn't do it (unless those specs take the ear into account, which, these days, they don't).

Minorl is touching upon what Ralph calls the power-paradigm/voltage-paradigm issue. Those white papers of his are illuminating regarding how amplifiers interact with loudspeakers.

I'm sorry. Who is Ralph? I would like to read his papers on the subject. Thanks,
To touch on a subject mentioned earlier. as long as we are using solid state/tube devices, wires, capacitors, inductors, etc. we will have propagation delay, distortion, losses, etc. I wish I was a smarter Engineer, I would go the star trek approach and things would be perfect. Using light as the signal, recording and playback media would probably be better. Digital is always flawed, although much better now, because it cuts an analog signal into pieces and then tries to piece it back together again. Sound is analog in nature. Eliminate the distortion, additions, and losses and you are there. I wonder where we will be 100 years from now? Quite honestly, we really haven't changed much in decades in amp design. Yes, the amps are actually built better. The transformers, capacitors, resistors, inductors, etc. are better. and the transistors are much better, more linear. Tubes? wow! I'm not sure if they are better or not. but amps? you still have input stage, high impedance, differential inputs, cascode, current mirrors, voltage gain, current gain, output drivers, etc. Bias control has gotten much better, and current sources are creative and better, but my point is like an automobile, what has changed? it is still an internal combustion machine that drives axles and wheels. Like I said, I wish I was smarter. I am absolutely cerain that Nelson Pass can design and build high quality tube amps also. A good Engineer is a good Engineer. He just choose to go the solid state route. Same for good tube amp designers. They can do just as well with solid state. They found their nitch(?) and went with it. However, to get to the level where you really listen to music instead of as background music is tough without spending an amazing amount of money. That is why used equipment sales are going strong. I'll take a Mark Levinson older amp Ml3, Ml2, Ml23.5, etc. any day. Threshold amps (replace the pre-drivers and output drivers with more linear transistors and wow!), Audio Research, etc. My point? This older equipment is wonderful! The good thing about a good Engineer like Pass, is that they can explain the difficult subjects clearly make it down to earth. There are many out there. I love reading their stuff.

Again, Enjoy

Enjoy

Minorl, of course there are electric cars too, and energy storage systems that are a lot better than the internal combustion guys would have you believe.

There have been improvements in amps in the last 50 years. There are new topologies that did not exist in the 1950s or 60s. So even if the parts had not gotten better (which they have) there would still be progress.

A lot of that progress comes out of the understanding of how the human perceptual system works. IOW we are not going to make progress if we design something to look good on paper, but the paper rules fail to take in how we hear sounds. Dr Herbert Melcher (famous in the world of neurochemistry) has done some recent studies that show that the more an audio playback system violates human perceptual rules, the more the processing moves from the limbic system to the cerebral cortex.