But my ear was closer than a desktop set-up when I tested. And "stuck with" is no answer. Why doesn't the manufacturer stick us with an amp that doesn't hiss? Is it just cost saving, or is there an inherent reason?
There are so many variables involved in being able to hear these extremely low levels of self-noise though. In the case of the JBLs, where it's sortof high, the whole package sells for far less than any actually good class D amplifier BY ITSELF. So I'm sure the reason is relatively high noise floor in the cheap amplifier they've used. And the advantages of their choice probably outweigh the other options with the same thermal, size, and power consumption characteristics.
For the better monitors, we are talking about noise levels several times below the normal domestic floor. Frankly, I think some people are just more sensitive to this type of noise than others. Pretty much all electronics make noise. I don't care about the noise my Vanatoo T0s make because it's lower level than the PC right next to them, and even solid state electronics make noise. Some people obsess over "coil whine", some people think it's practically a myth. All down to individual hearing and sensitivity.
My Magnepan 1.7is hiss connected to my living room signal chain of Denon X4500H -> External amplifier(
A Class D Audio SDS-470C). It's only audible if I'm right up against the panel at night when it's very quiet, but it's there.
I am curious if there is any detectable hiss from the studio monitors that use extremely expensive, top tier class D amps, like I believe the Kii 3s use Hypex modules. Not sure about the D&D 8C. There are some other very expensive actives that use Hypex Ncores, like the Grimm LS1.