I would add there are many crossover parts, mostly capacitors, that cannot pass small signals and/or very large ones. When a crossover can be made simple, this can be easy to hear unless the drivers are lame, which is another big problem. Duke, you allude to that in your comments about hearing those bass-guitar drivers compress the input signal.
When a completed speaker cannot pass small signals, for whatever reason, this means it does not pass low-level details. It produces what I call an ’On-Off’ sound, meaning the music has a ’Jump’ to it but lacks any Grace or Swing, two signals that are 'Small Changes'. Many audiophiles and designers are not wired to hear those, but let’s not go there.
When the delicate signals that an Atmasphere S-30 can pass are blocked by such a speaker, the music will be boring so that amp ’must not work for these speakers’. True-- the preferred amp, or cables, DAC, or preamp fills in those small-sound gaps with its less distinct, more smeared sound. Which is what one usually gets when an amp employs more and more output devices, for example.
I have heard smeared-sounding speaker wires be made more ’analytical’, more distinct sounding by using the same company’s interconnects. Used with all sorts of other speaker wires, those interconnects were clearly ’Off/On’ sounding. These were the only wires in this reference system, fyi. I have heard the same from some amps paired with their matching preamps.
Keep on listening!Roy