Dynamics at lower volumes?


Assuming appropriate source material, what technical characteristics of speakers/amps contribute to good dynamics at low to moderate volume levels? Are there are any speaker or amp designs that are thought to generally be inherently better at producing good dynamics at lower volumes?
midranger
Peter Walker (Quad) maintained that every recording has a specific volume at which it sounded best. Loudness controls are band-aids at best. I use a digital dynamic loudness control that I can program as I wish (a Tact DRC program). It is enjoyable, but does not restore what has been lost by using the "wrong" volume.
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I like your explanation,Samujohn. I had never heard it explained this way but it makes a lot of sense.
Peter Walker's unorthodox opinions are well worth studying. He did not believe in flat speaker response (try his roll off formula by using, say, Audacity to burn an equalized CD). He designed his speakers not to image in the listening room, but to approximate the sound of music coming through an open window.
My favorite was his comment when asked how far our hobby had come towards the actual sound of music. He snapped "about 15%"!
Horn speakers have a greater dynamic range than any other type, not only on the loud end, but also the soft end. Elizabeth's suggestion of the electrostats is the next best choice for soft dynamics.