Some years ago Logitech decided to get into the speaker business, so it bought up Labtec, a low to midrange speaker maker for the PC. Since that time Labtec has had a brand of its own, and has continued to designed products for the low end and midrange markets. The reason that Logitech bought out Labtec was that they needed the expertise that Labtec had in speaker design. Instead of releasing more low end products with merely the Logitech name, they decided to go all out with their first series of products. The Z-560 was one of their first smash hits, as it provided stellar sound at a very reasonable price. These are still a very popular set of speakers due to those above mentioned reasons, as resellers typically sell out of these products once they are on the shelves in a very short time.
While the first products were a success, there were many drawbacks to the design. First off the Z-560's were only a 4.1 sound solution, and the lower end version of these (the Z-540's) were also 4.1. The past year has been a time where 5.1 solutions have become the norm, and some of the best sound systems on the market feature this layout. Logitech could not stay behind here, and redesigned their product line with 5.1 in mind. The Logitech Z-640's are the budget 5.1 system for Logitech, and many of the lessons learned from their first entries show up with these.
Logitech did an excellent job with these speakers. The overall sound quality when compared to the price is perhaps the best in its class. For a long time I personally used the Creative Labs Inspire 5700's, and while their sound was average, I was fairly content with them. When I heard the Z-640's for the first time, I quickly had to get rid of the Creative speakers. The sound was significantly better, with a huge difference in the mid-bass and bass department. While the Creatives had the advantage of having a Dolby decoder with plenty of adjustments, the overall sound quality was quite poor when compared to the Z-640's.
--By Josh Walrath, source: Penstarsys.com
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