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

@atmasphere "target load in mind, which might be 4 or 8 Ohms” - in my 40y + sound works I haven’t seen such speaker, with purely resistive load (2/4/6/8/12/16)! In order to design output filter properly, we need to take complex model of loading, including variety of speaker cables, DC protection relay ckt, speaker crossover, spkr driver/s complex, often resonating impedances, which is tremendous engineering task! I’ve used class D amps in PA systems with active x-overs, where spkr was driven directly by the amp with short cable and w/o any x-overs in the path. For home use, I would definitely look for class D amps if I need power efficiency, that’s it. 

I like and have kept both. I’ve got a vintage Class A Pass Aleph3 (driven direct from a Wyred DAC2DSD) and ICE-based Wyred SX500 mono’s paired with a highly modified Rogue Metis (running Tung Sol VT99’s via adapters). The Aleph3 has an intimate continuity in image depth.. magical midrange while the Wyred’s (paired w my specific pre) have finesse and LF control while painting a detailed but natural cinematic stereo image. One is great for colder months and the other for summer and fall. I have tried the SX500’s driven direct from the DAC2DSD and thought it was nearly unlistenable, however. The right tube pre can have a way of ’sorting out’ older (but w well implemented output stage) class D topology into something that can still work now. The Rogue Metis Magnum is fairly dynamic (and a tube-roller’s dream/nightmare as an unbuffered tube design), but definitely a bit rough in stock form with stock tubes. I’ve got a good dozen other boxes in another room of other good-value separates; tube, Class D, and Class A, Class A/B, but these are the two setups I still use.. and I still go to shows. If I had money burning a hole in my pocket I’d like to try a Riviera Levante, Linnenberg or Kinki Mono’s.. a Nagra Classic amp.. perhaps some AGD Duets. I’d also like to try a Perla S50 integrated some day.. which I’ve heard with two way monitors before.

it’s more system synergy and implementation of the topology than topology, imho.

in my 40y + sound works I haven’t seen such speaker, with purely resistive load (2/4/6/8/12/16)! In order to design output filter properly, we need to take complex model of loading, including variety of speaker cables, DC protection relay ckt, speaker crossover, spkr driver/s complex, often resonating impedances, which is tremendous engineering task!

@westcoastaudiophile Actually its far simpler than that. A good class D amp can double power into a 4 Ohm load like any good class A or AB amp. There's no concern if the load isn't resistive! This is a no worries situation WRT the output filter.

In our case the amp is self oscillating, which means it also employs a lot of feedback. This prevents problems with capacitive or other odd loads causing resonance or the like- the amp is very well behaved with such loads as is any self-oscillating class D and so will be load invariant.