Logitech Frequency Directed Dual Drivers (FDD) Technology Explained
 

"It is not surprising to see multimedia manufacturers introduce newer technologies in the market to gain edge over the competition. After all, there are only a limited amount of aspects that you can alter and improve in order to make 2.1 and up speakers produce higher quality of sound. Few years ago, 2.1 speakers took over the market with a swish, but like everything in technology products tend to get outdated and common enough for users to demand something innovative and unique. We then started to see 5.1-surround sound speakers slowly emerge in the market."

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