The 5500's response is remarkably linear, even if the third-octave weighting does help. You should ignore the hiccup at 40 Hz, which is due to resonance in our room.
Covering all the useful bass range, the system's output in the lower part of the spectrum will obviously be one of its strong points...
As always, it's indispensable to start by carefully adjusting the different levels if you don't want to be disappointed. You can use the calibration system included in the Control Center or - above all for the subwoofer balance - recordings you know very well. Once we'd done this, the result was immediately very pleasing to the ear. The reproduction had very good neutrality, with a midrange that was precise and nearly free of coloration. You might find that the highs and mid-highs are a little less crisp and linear than with a good two-way system, but the full-range principle also has its advantages, providing a coherence that is truly pleasant to listen to. The bass kept its promises and was both deep and powerful while maintaining good definition. Do take care not to give this system its head too much, because it can rapidly become a mite too exuberant! With careful adjustment, the results with highly rhythmic music were really very good, reproducing all the musical content. With high-production-value movies with many loud, special effects, the full-range speakers provided very good reproduction of dialogue and the subwoofer delivered all the punch needed for those who like to feel and hear explosions rumble and gunshots fired. However, look out for your neighbors, who might not want such special effects vibrating their walls and floors when you crank up the 5500's volume to see what it is made of.
The improvements over the previous model are quite positive, and the Logitech Z-5500 is a model particularly suited to enthusiasts who want to reconcile sound quality and spectacular output. Among our reservations are certain items missing from the Control Center (standards and connection) and also the fact that the new version didn't choose to use two-way satellites. But as it stands this is a system we can enthusiastically recommend.