Are future improvements in Amp/PreAmps slowing to a crawl?

"If we all worked on the assumption that what is accepted as true is really true, there would be little hope of advance."

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Roger

I see two things improving these days, DACs and class D power amps.

Other than incorporating new, more capable DAC chipsets into new preamp models, I agree with others who have posted here, that the preamp itself isn't really improving.  In my case, I have never used the DAC in my preamp, I went with an external unit, one based on an FPGA chip, where firmware updates improve the performance of the DAC, like getting a "new" unit every year or so!

I must admit that it's been years since I auditioned a class D power amp, and back in the day, was not impressed with the sound (to me it sounded "brittle").  With all the new class D designs, eventually I'll take the time to update my experience with class D and audition some of the new amps.

The problem with most DACs is not the chipset on the front-end.
It is the analog stage that follows. The digital data to be converted to analog far out strips the ability of the analog section to pass along the stored image.

" the preamp itself isn't really improving "
This was true up until now.

The digital data to be converted to analog far out strips the ability of the analog section to pass along the stored image.

This statement is false.