I had a question related to Class D

It seems odd to me that a manufacturer would post output specs at 10% THD. Who cares?

Why wouldn't they publish specs for a listenable THD?

The chips are not meant to be 'high end' FWIW. 100 watts is where the amp clips and at that point its making 10% distortion. So that is the spec they published.

but I heard that Class D amps lose a lot of their power (more than Class A or A/B amps do) when they drive speakers above 4 ohms, and my speaker happens to be 8 ohms. Is this so?

@bryant11 

No. Most solid state amps will make less power into higher impedances. So you have to look at the 8 Ohm rating to see how much power the amp makes into that impedance. Driving 16 Ohms will further cut the power in half... you see how this works? Its not a 'class D' thing.

IMO if you are planning to use this for guitar, you'll be better off with a tube guitar amp of about 25 Watts. I think you'll find that it plays just as loud but is a lot more musical.

It seems odd to me that a manufacturer would post output specs at 10% THD. Who cares?

Why wouldn't they publish specs for a listenable THD?

My Parasound New Classic 200 Integrated uses Pascal D modules outputting 110 wpc with .05% THD @ 4 or 8 ohms.

They publish a 1% THD as well, but I don't care that if outputs 125 wpc at that THD level... it just tells me not to turn it up to 90-100% volume.

This D amp can get way louder than I'll ever need with 8 ohm, 87 dB speakers with the volume at 35-40%.  No power dropping off with 8ohm speakers. I'm guessing that story is from older D amps.

The issue are not the amps but the power supplies feeding them. For some reason, class D manufactureres skimp on the PSUs.  If you get one with a powerful large toroidal unregulated PSU, they will not run out of steam. 

That is not my experience. My 500 w/ch Class D amp never runs out of gas and never even breaks a sweat even at very high spl with average efficiency speakers. My 40 watt Class D amp that’s the size of a pack of cigarettes (Fosi, see system pics) drives kef ls50s no problem which is beyond what I expected.

My experience is that in practice, class D amps generally sound about half as powerful as an AB counterpart of the same power rating. This isn’t to say that will be the case with any class D amp, but it’s a pattern that was prominent in the early 2000s and seems to persist today. It seems as though many class D designs struggle with full bandwidth power, at least that’s how they usually sound to me — a prevalence of sounding thin in the two lowest octaves.

The only class D amps I’d ever consider are those anchored by the Purifi modules and possibly some Bel Canto models.

Specs say 80 watts into 8ohms at 10% distortion. Just guessing but the 1% distortion level will be quite a bit lower so it's not a real powerhouse.