Amplification: what are the biggest advances of the last 40 years?


As an audiophile most of my adult life but without any engineering expertise, I wonder how amplification has advanced since I started in this hobby as a high school student in the eighties?

Specifically, what has advanced the state of the art and what, specifically, make newer products sound "better" than older ones?

Is it that circuit design has advanced so much?  Or is the bigger difference parts quality and the technology leading to these better parts?

And please, none of the banal "it all matters" comments.  What I'm asking: which of the above matters the most?


bobbydd
@bobbydd  

I inquired as to why the new amplifier we were listening to was so expensive?

The parts and labor that go into a quality point-to-point constructed amp are incomparably expensive vs 60 years ago.  Mass produced, PCB-based HT receivers can be churned out much less expensively (relative to inflation) than products even in the 70s.
@bobbydd
The reply was something to the effect that "well, the technology and parts quality of these newer generation " units are far beyond what was possible a few decades ago. Also, that circuit design has advanced tremendously as a function of technology.
This is a valid statement. Although it’s not a stark change like the discovery of semiconductor chips, high-end audio is uses both technology and art. In our small niche high-end audio market, intense competition leads to increasing better sonic designs over time. Take prolific amplifier designer Nelson Pass for instance- his decades of designing experience has influenced his current offerings. Also, the quality of audio transformers have made significant sonic improvements.

Even internal parts can be very expensive such a Takman, Vishay, Mundoff, to name a few. Custom transformers can also be pricey. 
Also with better audio component designs (like speakers), we are better able to hear differences in the quality of amplifiers. 

That’s why we pay (and sometimes pay n pay n pay…) for these sonic improvements.

And please, none of the banal "it all matters" comments
The entire audio chain matters, but one’s system must be resolving and transparent enough to hear the differences such as to the “fool you it’s real” level. While one can throw in a quality amp and gain sonic improvement, if the rest of the system is not to the same quality level as the new amp then the rest of the system is holding back what the amp is capable of performing.
The biggest advantage to better components in the last forty years was the advent of the compact disc and the dvd and blue ray which caused the amplifier to put out more power and dynamics to meet the demands for the new mediums. The other key components have all taken a step back in technology and sound since the start of the ipod era because of the advent of computer style electronics instead of audio grade eletronics. As for speakers they have all taken a backwards turn since 1965.
During a recent visit at my local dealer, I inquired as to why the new amplifier we were listening to was so expensive?
@bobbydd  High end audio isn't about price, its about intention. It is true that better parts are more expensive than parts of lessor performance. Its also true that low production numbers increase price. Finally there's something called the 'Veblen Effect' where a higher price tends to convey a perception of higher quality. Usually its only a higher price though. Companies that price according to a formula tend to have less expensive product than those that price according to what the market will bear but can quite easily offer higher performance.


One of the biggest audio debates in high end since before the www is the tubes/transistors debate. The reason tubes are still around is that most transistor amps are harsh and bright (entirely due to distortion and the misunderstanding that many people have that the low distortion is 'inaudible' when its obviously not; there's been a bit of denial going on...). Class D has brought the ability to build a solid state amp that isn't harsh- thus sounds just like a good tube amp without some of the bandwidth problems that are often a problem with tubes (especially higher powered tube amps).


As a designer of high end audio power amplifiers I see this as the single biggest advance in amplifiers in the last 50 years.
Some audiophile friends and sales people are of the opinion that "older amplifiers are outdated' and therefore cannot compete with the better new high end amps".

Personally, I'm skeptical of such statements, hence my original post.

Is it true that the best newer amps always sound better than the best older units?  

Does either technology, better parts, or improved circuitry and engineering make such progress inevitable?

I have not personally compared many units of different vintages in my system to answer that question.  Maybe some here have?