What creates the effortlessness in sound reproduction?


Hello, 
I have a chance to listen some speakers in the last 10 years. I notice that there are 2 speakers which produced sound 'effortlessly', even at low or high volume levels (I never tried max levels on them since they are not mine). With this effortlessness, listening to music is very relaxing. 

I wonder what makes the effortlessness in these speakers? 

Please shed some light on this. 

Thank you. 
Huy
Ag insider logo xs@2xquanghuy147
@erik_squires : I checked Gik Acoustics, should I go with bass trap or diffusion panels, how to decide which one I need?  I read some articles online but they are pretty 'technical' for me.

Could you give me a hint or direction? I am living in carpeted, small room 16ft x 16 ft with a pair of Devore Nines. 
Thank you
Huy
Hi Huy,
Talk to them. They'll help you get set up. Have a budget in mind. :)

They are really pros at this.  I'm an amateur by comparison.

Best,
E
As geoffkait indicated, but, in two words, dynamic range. Every listener, should have some experience, to listen to live, unamplified music, to get an understanding of what dynamic range, really is. ( real musicians, in a real space ). I am speaking of music and sound, as dynamic range is also associated with  vision ( photography.and video ).
I'm sorry for my ignorance but I am not sure I understand this correctly. Do you mean that in an experiment of several systems which are playing at 100dB, some system will be louder than the rest?
@quanghuy147  No. Some systems will **sound** louder. This is because higher ordered harmonics are used by the ear to sense sound pressure. If a system is making more of them than a 2nd system, that 1st system will sound louder even though it isn't. In fact this is so profound that the 1st system could be a good 15dB quieter and still sound louder.

Eliminating intermodulations and higher ordered harmonic distortion is the key. 
Larger drivers being slower is a misnomer. Often smallish drivers are wrongly claimed to image better, sound quicker, etc. It's mostly attempted justification for a lesser rig. Listen sometime to how much distortion a 6.5" woofer puts out in comparison to 15". I prefer not to introduce that level of distortion into low end performance. :)
As usual, YMMV