Why would anyone want class AB amp when class A always sounds better ?

As a casual listening “semi-audiophile,” my journey took a delightful turn when I started digging through the story of the early Crown SS pro audio amps. I ended up scoring two PS 200s in decent shape for under $200 each, sent them back to them back to the Midwest for refreshing and thoroughly enjoyed building two different systems...a 6U rack system with modern processing and vintage Cerwin Vega/Jensen sub speaker combo...and the other a “rat rod” rig with nothing but an unpowered Shitt preamp and BT2 Bluetooth DAC with modern REL T5I sub and Onkyo towers both running off high output.

We don’t play much volume around our home and cottage, so these venerable refurbished 90W Class A/AB/A+AB Crowns, both removed from churches, run in crisp Class A most of the time and present a surprising snd pleasing sound stage. Great fun and great value in the final analysis, FWIW

...and yes, they help heat our respective living rooms :)

Hi audio2design, go and pick up your Nobel.

You have designed an amplifier that is 100% efficient.
Not possible.

Although Class D is the first amplifier topology that theoretically offers completely linear operation with 0% distortion and no power loss at 100% power efficiency, the commercialization of Class D audio amplifiers had to wait until the ‘90s when silicon (Si) MOSFETs with sufficiently good device parameters became widely available.

https://www.powerelectronicsnews.com/opening-up-the-next-chapter-of-class-d-audio-amplifier-performa...

I saw theoretical max in the post. 

Since this is all subjective I wouldn't trade classD for classA  as long as each amp were designed properly and were used within their parameters. 

Just buy whatever sounds best to you..  Glad we have choices..
I will stick with Class A amps as they provide the best sound to my ears. I agree with @atmasphere , The topology is simpler, but requires a better PS and ways to manage heat. Those who buy based on efficiency alone are missing out..