Audio advancement - why?

Because size matters!

Sony can't build a walkman with tubes inside, same goes for 99% of mass market audio gears out there. Imagine if Sony had to build a 5-channel HT receiver with tubes, it will take up quite a bit of floor space.

Same goes for media. Reel-to-reel, LP, cassette, CD, MP3, and who knows what's coming next. Each generation degrades the sound, but 99% of people out there don't care because they can carry more garbage with them everywhere they go.

Let me take a shot.
Music reproduction has to do with your ears and physical feeling in a room with it... Not complex number crunching storage devices, or flying an airplane.

So realistically your ears today or in 1950 would have been the same. Advanced audio today has to do with cheaper, better, faster, more reliable ways to keep it in your house more than anything, along with heat and efficiency, reliability. Not so much to how it sounds. The best guitar amps, pro studio equipment etc... still run on tubes, but there is also excellent or better solid state in some areas of audio depending how much your willing to spend.

This question and hobby unfortunately is totally disconnected from the standard "why has it not advanced" theory. Vinyl is crude and 90% of the time easily the recordings best the BEST sounding IPOD in the world! IPOD is advanced, its solid state, doest that mean it should beat a 10,000 dollar tube preamp and amp? Nope.

Video easily is explain as again video is seen, you can put one next to the other and compare with virtually no question from person to person. Audio is a whole different world and brain function, of course if you have bad eyesight and put on glasses all of a sudden you see things in high definition, of course if you are flying an airplane the best thing is reliability and accuracy not flying with vibration and failure sensitive tube devices.

Again has nothing to do with audio or the reproduction, heat, tubes, and analog period is how your ears work, digital and solid state are simply copies of reproducing it more efficiently but not necessarily better in all cases, faking it and making them as close as possible is all we are doing in home anyway, should a violin, grand piano or drum kit be solid state? Or should it still just create sound based on mechanical vibration? That of course has nothing to do with Tube vs. solid state, however reproducing it can.

Anyway bottom line is your ears work the same either way, what works for you? Natural sound can be had many ways, nobody has an answer to the best for every situation, but for sure the more artificial you make it sound, the less involving it can get, tubes and vinyl for example keep everything in the analog realm with no conversion, so it appeals to some more. But they have not necessarily discounted or realized you can in fact get similar or better results with "Higher" technology.

Solid state technology DOES have an answer to the imperfections of transistors cited by Atmasphere. Digital amps. (You could make a digital amp using tubes, but there would be no point to it). In a digital amp the output devices are full-on or full-off, so their linearity is a non-issue. The analog output is modulated by the duty cycle (ON/OFF timing) of the output devices, and there is no limit to the accuracy achievable, except cost.

Undertow said:

Advanced audio today has to do with cheaper, better, faster, more reliable ways to keep it in your house more than anything, along with heat and efficiency, reliability.

I think this is the answer in a nutshell. I don't think the early engineers said "let's develop SS because it sounds better." But, rather, the bean counters told the engineers to develop a way to produce electronics faster, cheaper and with greater reliability.

Eldartford, what you say is partially true- the problem is that the distortion signature still enhances odd-ordered harmonics.

Milpai, humans *were* able to make advances in audio- and it turns out that tubes are the way to do that- appropriate technology IOW.