In a brief in house audition I did with ls50s a while back, I found bass performance was very amp and room dependent.
Sounded great in smaller room with high current high power (500w/ch 8 ohm) low output impedance Class D amp (Bel Canto ref1000m), was very underwhelming in a larger room with lower current, higher output impendence, 180 w/ch 8 OHM SS amp (TAD Hibachi), much more so than other similar size smaller monitors I have tried.