Has anyone switched from Class AB/A to Class D? Was it better? Was it worse?

"Think of BMW - they make various models and then they offer the M series. What is the difference."

The BMW M series’s original intent quickly diverged to a "M = Marketing" strategy to sell more upgraded BMW’s to those desiring the M badge of honor.

Originally, BMW had to sell a minimum number of street-legal cars to qualify for the European Motorsport series. They were true street-legal race cars at first and they sold out quickly. That is when the BMW marketing dept. realized an opportunity to increase profits. The M cars of today are far from the original spirit of M.

In the audio world, we see this sometimes with upgraded casework that gives the audio-jewelry effect that if it looks good, it must sound good, just like with the M-series’ aggressive styling and colorful racing stripes. Anyway.

In my case, better.  After the second repair of my 65 lb. Odyssey Stratos amp, which required lugging it to and from shipping facilities, I gave up after it failed a third time.  I was determined to find something powerful, yet much lighter.  My solution was Mike Kallelis' Arion Audio S500 stereo Class D amp.  It was more powerful, at 500 watts per channel, than the Stratos.  But the big surprise was the excellent synergy between the S500, my McIntosh C220 tube pre, and my Ohm Walsh 2000 speakers.  An annoying peak at about 7kHz, which I had attributed to the Ohms, vanished.  The Arion might be very slightly more neutral and less warm than the Stratos, but the elimination of that peak was worth way more to me.  I have had the amp for 6 years now, with no issues and no interest in upgrading it.  It runs cool, and weighs only about 22 lbs.  A very good value, too, IMHO.

Starkrimson 25 Mono Premium - Amplifer Tour | Steve Hoffman Music Forums

Try it for yourself.

@dman777 I used class D amps for 80kW front end PA gig setup, and I am using AB/A class amps for home sys.. class D has too much harmonics at low output level, RF noise, “weird” pulse response.. 

I came from an AT 6007 Signature Series amp to class D Legacy Audio V:I Amplifiers. At the same time, I went from Marantz 8805 to a Lyngdorf MP-40 processor with Room Perfect. The ATI weighed hundreds, and the Legacy weighs much less, but does it ever pack a punch. Plus, it runs cool with absolutly no buzz, no hiss. I love the combo