Gallium Nitride GaN Class D Amplifiers

No experience with Orchard or AGD, but I owned a pair of Atma-Sphere M-60s for a number of years, fully upgraded to 3.3 including V-Caps. After procuring a pair of the Atma Class Ds, the M-60s were sold and I've never looked back. The Class Ds are smoother in the top end, have better control of the bass, and are equal in the midrange, all of which is high praise as the M-60s sound great. I don't at all miss the heat output or the 24 tube anxiety of the M-60s; the Class Ds never even get warm, and I can leave them on all the time.

Speakers are Zu Druid V, which I've driven with 2 watts but sound way better with 50, regardless of room size.

@atmasphere Respect and regards to you and to Alberto.

Please, it is not bass I am referring to but low-end reverb(?). The two tracks I previously mentioned involve a synthesizer and organ, not bass guitar or other. I own a pair of REL 212SX and yes, Billy Eillish tracks and others hit my chest like a truck. What I am describing is the emotion of deep notes, resonance (reverb?) that you can feel. My Accuphase A36 and PASS LABS x260.8s knocked those tracks out of the park, but were muted... benign with GaN. If this piece can be solved by GaN amplifier manufacturers, GaN will be my last stop. That said, I will soon be auditioning a new player in the GaN space (ArgentPur) some time this month or so.

@izjjzi I can't speak for other class D designs. The sound varies from one class D to another more than it does with class A amps or tube amplifiers- IOW quite a lot.

But I know how our stuff sounds.

For reference I use LPs and CDs that I recorded- which helps since I know how they are supposed to sound. The bass issue you seem to describe doesn't sound challenging to me- I also play bass and keyboards (most of which are old school synthesizers) if that helps...

I believe Most Class D amps have low output impedance which can contribute to damping factor compared to higher output impedance tube amps. That can make a big difference in how bass sounds in many cases (not all) in that the driver is better controlled and distortion lower. When I first heard my first Class D amp in my system, Bel Canto ref1000ms, it sounded like the bass was gone. Shortly after when my ears adjusted I realized it was all there but more defined and articulate than ever compared to several prior SS amps. A decent quality sound meter app is all that is needed to put any bass level question to rest. Ears alone may well not cut it in this case.

@mapman +1, I also own the Bel Canto REF1000Ms and use them to power my distributed bass array for a bi-amp set up. No shortage of bass there and it's very fast and articulate.

When speaker designers of yore were making speakers with 32 and 16 ohm impedance damping wasn't quite as important. Back then tube amplifiers, zero feedback SET in particular known for high output impedance, were by far the norm. Nowadays with speakers being of lower impedance things have changed. It's been said by a few people I know who make tube amplifiers that the popularity of solid state amplifiers using feedback came about due to speaker designers making 4 ohm impedance speakers. Makes sense when you think about it as damping should be higher with that type of load. However, these same tube amplifier makers have said to me that anything over a damping factor of 20 makes very little if any difference. So the damping factor spec should be taken with a grain of salt as well.