Our first test for the Z-4s was musical. We pumped Death From Above 1979's "Blood On Our Hands" at the speakers' highest possible volume, with the subwoofer cranked all the way up, just for kicks. Shockingly, there wasn't a smidge of speaker distortion, despite the fact that we had the low range set to an inappropriately high volume for music. At a more sensible subwoofer level--about one o'clock on the dial--the song sounded crisp in the high-mids and deep in the lows, with the thunderous kick drum never getting too muddled. At times, however, the subwoofer sounded disconnected from the satellites, a common issue with computer speakers that avoid using woofers and go straight to the subwoofer. The absence of a regular woofer means some frequencies, namely low-mids, get a bit less attention than they deserve.
This minor quality issue is rarely a problem for movie watching (unless you're watching a musical), as the frequencies that matter are dutifully represented by a good subwoofer and capable satellites. The Logitech Z-4s did an admirable job with The Life Aquatic's subtle sound mix (in which guns and explosions sound like real guns and explosions, not 50-foot cannons) but could have provided a bit more rumble in the low-end ship noises and weaponry of Star Wars II: Attack of the Clones. Still, the rumble was not absent, and clarity prevailed, another improvement over the Z-3s. For the gamers out there, this set may be a bit light in the rumble department; the explosions in Escape Velocity Nova never distorted at even the highest volume, with the sub on max, but they didn't exactly send shudders down our spines like Logitech Z-2300s did. That gap in the low-end intensity between the Z-4s and the Z-2300s is why the latter set remains our benchmark for 2.1 quality.
Logitech addressed the gripes we had concerning the Z-3s' remote and scores points with the Z-4s' improved remote. The company also did well to switch to a different type of satellite design. The addition of two drivers per speaker has definitely improved clarity in the low-mid and high-mid frequencies. The dual drivers take the pressure off the modest subwoofer and make the satellites the main reason to own the set, as they should be. Gamers and film buffs who care only about rattling their walls with low-end thunder can find a more powerful set elsewhere, but if you value a balanced mix with an emphasis on clarity, the Z-4s are a great option, and at $100, worth every penny.
Logitech Z4:
