Proac One SC - Do thet perform well at low volume?

My experience - low volume SQ is heavily dependent on the amps ability to provide a healthy enough signal that the speaker can put out a refined bass without the need for enormous power. Interestingly given your ProAc question is that I run a YBA Passion integrated to ProAc D15's and have very nice low volume SQ, and I don't think my ProAc's are that efficient.  

Something else to think about...

Doesn't the amp play a role in low volume performance ?

Something like PP amps usually sound better turned up just a bit where as SET amps do best when barely turned up (that 1st watt thing for SET's) .

Anybody ?

Agree.

I would include solid state true Class-A/SIT's as well, besides SET's, to achieve the advantage at lower power. SET's are said to operate to the most desired effect well within (i.e.: somewhat below) its stated max. power output, which, given it's usually limited to 5-10 watts (or even lower), would require seriously sensitive speakers (>97-98dB) for this to come to fruition - all relative to the size of the listening room, acoustics, individual SPL requirements, etc. Even with 20-40 watts SS true Class-A amps (not incl. the less powerful SIT dittos), relatively sensitive speakers are called for. My impression is that, generally, the more sensitive the speakers the better their abilities into low level detail retrieval, and this seems to go hand-in-hand with SET's, SIT's and other SS Class-A variants.

Usually when speakers are on the lifeless side at lower volumes I tend to find them dull sounding even at higher volumes, and so typically it’s a give-away. The ability to "ignite" sonically at lower volumes (in retrieving detail resolution) is one of the core traits I’m looking for with speakers, and it’s not related to any "smiley" loudness effect - almost on the contrary; I would find it’s attributable mostly to the frequency spectrum from the upper bass to the lower tweeter region without a reverse "smiley"-effect, but rather one of presence and energy. When paired with this is the ability to maintain tonality up through very high SPL’s, then we’re talking something very special indeed.

So I guess my advice would be to actually pay close attention to any speaker’s abilities at lower volumes, and where positive see them as possible traits in the greater scheme of things (i.e.: at higher volumes as well).

Thanks Wolf - Consider that "proximity to the speakers" theory under consideration.

Note that if a speaker sounds great at low volume (although this is relative…begging the question, "what do you consider low volume?") it likely has a frequency response tilted toward exaggerated highs and lows, and may not sound so good at "regular" volume. An unavoidable part of the physics of sound reproduction. Think of a graphic response curve looking like a smile (JBLs from the 70s) and you can get why some preamp circuits contain a "loudness" compensation eq for exactly that sort of thing. My recommendation for low volume listening is to sit closer to the speakers.